CompTIA Tech+ (FC0-U71) · glossary

Tech+ glossary

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2.4 GHz

The Wi-Fi band with the longest range and best wall penetration, but slower and crowded with interference. Lesson: Band options: 2.4, 5 and 6 GHz

5 GHz

A Wi-Fi band that is faster and less crowded than 2.4 GHz but covers a smaller area. Lesson: Band options: 2.4, 5 and 6 GHz

6 GHz

The newest Wi-Fi band: fast and uncrowded but shortest range. Only Wi-Fi 6E and newer devices can use it. Lesson: Band options: 2.4, 5 and 6 GHz

A

Access control

The OS job of deciding who can sign in and which files and resources each user may use. Lesson: Managing devices and access

Access point

A device that lets wireless devices join a wired network by Wi-Fi. Adding one extends Wi-Fi coverage. Lesson: Access points and firewalls

Accessibility

Features that make devices easier for everyone to use, like zoom, larger text, captions and screen readers. Lesson: Accessibility and appearance

Accounting

Tracking what users do, mostly with logs, so you can see later who did what and when. Lesson: Accounting and nonrepudiation

AI assistant

An AI that works for one person and takes actions across apps and devices, like setting reminders or sending messages. Lesson: Chatbots and assistants

AI chatbot

An AI that holds a typed or spoken conversation and answers questions, like a help chat on a store's website. Lesson: Chatbots and assistants

AI predictions and suggestions

AI that uses patterns in past data to forecast what will happen or recommend something, like 'customers also bought.' Lesson: Predictions and suggestions

AI-generated code

Code written by an AI tool from a description. It must be reviewed, tested and checked for licensing before use. Lesson: Generative AI

AI-generated content

Text, images or other content made by generative AI from a prompt. Check company policy and whether it copies others' work before using it. Lesson: Generative AI

Anti-malware

Software that finds, blocks and removes harmful software. Keep it on and up to date. Lesson: Securing phones and workstations

APFS

Apple File System: the filesystem macOS and iPhones use. Lesson: File system types

App store

An official app store that checks and scans apps, making it the safest place to get apps for a device. Lesson: Where software comes from

Appearance

Settings that change how something looks, like browser themes and dark mode. Lesson: Accessibility and appearance

Application management

The OS job of installing, updating, repairing and removing apps. Lesson: Managing disks, tasks and apps

Array

An ordered list of values stored under one name. Each item has a numbered position (index), usually starting at 0. Lesson: Arrays

Assembly language

A low-level language where each short code, like mov or add, stands for one instruction of a certain CPU family. Lesson: Query and assembly languages

Attenuation

A signal getting weaker as it travels farther or passes through walls and other objects. Lesson: Why signals get weak

Attributes

Another name for a property: data that describes an object. Lesson: Objects: properties, attributes, methods

Augmented reality (AR)

Digital images laid over the real world you still see, through a phone camera or smart glasses. Lesson: Consoles, VR and AR

Authentication

Proving who you are, for example with a password, a fingerprint or a code from your phone. Lesson: Authentication

Authorization

Deciding what a signed-in user is allowed to do or open. Lesson: Authorization

Availability

Making sure people can reach data and services when they need them. Lesson: Confidentiality, integrity, availability

B

basic input/output system (BIOS)

Firmware that runs first at power-on: it checks the hardware and starts the operating system. UEFI is its modern form. Lesson: Firmware and the BIOS

Big Data

Data so large, fast-arriving or varied that normal tools cannot handle it, like millions of clicks and sensor readings a day. Lesson: Analytics, big data and monetization

Binary

Base 2: numbers written with only 0 and 1. Each place is worth twice the one to its right (1, 2, 4, 8 and so on). Lesson: Binary: only 0 and 1

Bit

The smallest unit of data: a single 0 or 1. Network speeds are counted in bits per second. Lesson: Bits and bytes

Bits per second (bps)

The basic unit of data speed: how many bits move across a link each second. A lowercase b means bits. Lesson: Throughput: bits per second

Bluetooth

Short-range wireless that links devices across a room, like headsets, keyboards, mice and speakers. Lesson: Wireless: Bluetooth, NFC and Wi-Fi

Bookmarks

A saved link to a web page so you can return with one click. Bookmarks can be sorted into folders. Lesson: Sync and bookmarks

Boolean

A data type with only two values: true or false. Comparisons like weight > 50 give a Boolean. Lesson: Every value has a type

Branching

Choosing one path based on a condition, as in IF ... THEN ... ELSE. Only one path runs. Lesson: Branching and looping

Browser extensions

A small add-on that gives a browser a new feature. Also called an add-on. Install only from the official store. Lesson: Extensions: add, remove, enable, disable

Byte

A group of 8 bits, enough to store one simple character. File and drive sizes are counted in bytes. Lesson: Bits and bytes

C

Cable

Internet service over the coaxial cable used for cable TV. Neighbors share it, so it can slow at busy times. Lesson: Fiber, cable and DSL

Cable lock

A steel cable that ties a laptop to something solid so it cannot easily be carried off. Lesson: Securing phones and workstations

Cable tester

A tool that checks a finished cable, confirming each wire reaches the right pin. Lesson: Crimpers and cable testers

Cache

Copies of page images and files a browser keeps so sites load faster. Clearing it can fix pages that look broken. Lesson: Cache and pop-up blockers

Casting

Sending one video, tab or song to a TV or speaker to play, instead of copying your whole screen. Lesson: Mirroring vs. casting

Cellular

Internet from a carrier's towers to a device with a SIM card, so it works on the move or anywhere with coverage. Lesson: Wireless: RF, satellite and cellular

Central processing unit (CPU)

The processor that runs program instructions and does the computer's general work. Its speed is rated in GHz. Lesson: Processing and storage

Char

A data type that holds exactly one character, like A, 7 or a space. Lesson: Every value has a type

CIA triad

Confidentiality, integrity and availability: the three main goals of information security. Lesson: Confidentiality, integrity, availability

Cipher text

Scrambled, unreadable data made by encryption. Only the right key turns it back into plain text. Lesson: Plain text vs. cipher text

Class

A template for making objects of one kind, like a Product class that every product object is built from. Lesson: Comments, documentation and objects

Clearing the cache

Deleting the browser's stored copies of page files. It fixes pages that look stale or broken without signing you out. Lesson: Cache and pop-up blockers

client/server

A network model where central servers provide services and the other computers (clients) use them. Lesson: Client/server and peer-to-peer

Cloud

Running systems in a provider's data centers and reaching them over the internet, instead of on the company's own hardware. Lesson: On premises, cloud or hybrid

Cloud storage

Storage run by a provider in its own data centers and reached over the internet, so you buy no hardware. Lesson: Cloud storage

Cloud storage service

Storage run by a provider in its own data centers and reached over the internet. The exam lists it with NAS and file servers as network storage. Lesson: Local network and cloud storage

Collaboration software

Apps for working with others: email clients, conferencing, online workspaces and document sharing. Lesson: Collaboration software

Command-line interface (CLI)

A text interface where you type commands and read text replies. Lesson: GUI or command line

Comments

A note inside code that explains it to people. The computer ignores comments when the program runs. Lesson: Comments, documentation and objects

Compatible browser

A browser that a web app supports. If an app says 'browser not supported,' open it in one from its supported list. Lesson: A compatible browser

Compiled language

Code translated ahead of time by a compiler into machine code. The result usually runs faster and needs no interpreter. Lesson: Compiled or interpreted?

Compression

Making files take less space. Filesystem compression keeps every byte, so apps open the files normally. Lesson: Compression and encryption

Compromised content

A real file, site or app that an attacker has changed or taken over so it now carries harm. Lesson: Malicious or compromised content

Conferencing

Software for live meetings with audio, video and screen sharing. Lesson: Collaboration software

Confidentiality

Keeping data readable only by the people allowed to see it. Lesson: Confidentiality, integrity, availability

Console

A text window for typing commands, also called a command line or terminal. Lesson: GUI or command line

Constant

A named value that is set once and cannot change while the program runs. Lesson: Identifiers: variables and constants

Constraints

A rule a database enforces on every save, like not empty or price must be zero or more. Lesson: Constraints

Cookie consent

A website asking your permission before it stores cookies it does not need to run, such as tracking or ad cookies. Lesson: PII, GDPR and cookie consent

Crimper

A hand tool that squeezes an RJ45 plug onto the end of a network cable. Lesson: Crimpers and cable testers

Critical data

Data the business cannot run without, like orders waiting to ship. It is protected and restored first. Lesson: Data as an asset

D

Data analytics

Examining data to find patterns, trends and the reasons behind them. Lesson: Analytics, big data and monetization

Data at rest

Data that is stored, like files on a drive or photos on a phone. Lesson: Data at rest

Data availability

Being able to reach data when you need it, whether it is stored locally or in the cloud, online or offline. Lesson: Persistence and availability

Data capture and collection

Gathering new data to use later, such as saving answers to a question at checkout. Lesson: Data-driven decisions

Data correlation

Finding that two sets of data move together. A correlation does not prove one thing causes the other. Lesson: Data-driven decisions

Data in transit

Data that is moving across a network, like an email being sent or a web page loading. Lesson: Data in transit

Data monetization

Earning money or other value from data, like selling anonymous trend reports or using purchase history for offers. Lesson: Analytics, big data and monetization

Data persistence

Data stays saved in storage after the app closes, the server restarts or the power goes off. Lesson: Persistence and availability

Data type

The kind of value a piece of data is, such as a char, string, integer, float or Boolean. It decides what you can do with it. Lesson: Every value has a type

Data-driven business decisions

A choice based on real data and trends instead of guesses or opinions. Lesson: Data-driven decisions

Database

An organized collection of data that many people and apps can search, add to and change at the same time. Lesson: Flat file vs. database

Database uses

What people do with a database: create tables, import or input data, query for what they need and build reports. Lesson: What you do with a database

Decimal

Base 10: the everyday number system, with the digits 0 through 9. Each place is worth ten times the one to its right. Lesson: Decimal: the one you already know

Default search engine

The search site that address-bar searches go to. An unexpected change can mean an unwanted extension. Lesson: Search engine and password management

Default usernames and passwords

The factory login a device ships with, like admin/admin. It is the same on every unit and easy to find online, so change it during setup. Lesson: Defaults and enabling passwords

Device management

The OS job of detecting hardware, loading the right drivers and keeping them updated. Lesson: Managing devices and access

Device Manager

The Windows tool that lists hardware, shows problem devices and lets you update or roll back drivers. Lesson: System apps and utilities

Digital subscriber line (DSL)

Internet service over existing copper phone lines. It gets slower the farther you are from the provider's office. Lesson: Fiber, cable and DSL

Digital Visual Interface (DVI)

An older video port that carries a digital picture but no sound. Lesson: VGA, DVI, HDMI, DisplayPort and USB-C

Directories

Another name for a folder. Lesson: Folders, paths and naming rules

Disk management

The OS job of preparing drives: initializing them, creating and formatting volumes and assigning drive letters. Lesson: Managing disks, tasks and apps

Disk-level encryption

Encrypting a whole drive, so everything on it is unreadable if the device is stolen. Lesson: Data at rest

DisplayPort

A digital video port, common on PCs and monitors, that carries video and sound. Lesson: VGA, DVI, HDMI, DisplayPort and USB-C

Document database

A non-relational database that stores each record as a document, usually JSON, and can search fields inside it. Lesson: Key/value and document databases

Document findings, lessons learned, actions and outcomes

The last troubleshooting step: write down the cause, the actions you took, the outcome and the lessons learned. Lesson: Step 6: Document

Document sharing

Keeping one copy of a file online that several people can view or edit, often at the same time. Lesson: Collaboration software

Documentation

Written explanations of what code does and how to use it, for the people who use or change it later. Lesson: Comments, documentation and objects

Driver

Software that lets the operating system talk to one kind of hardware, such as a printer or scanner. Lesson: Plug-and-play vs. driver installation

Driver installation

Installing a device's driver by hand, usually from the maker, when the OS can't load one by itself. Lesson: Plug-and-play vs. driver installation

E

e-reader

A device built mainly for reading books, often with an e-ink screen that is easy on the eyes and a battery that lasts weeks. Lesson: Phones, tablets, e-readers and laptops

Email

Messages sent between mail servers and read in an email client or web browser. Lesson: Where privacy leaks

Email client

An app that connects to a mail account to read, write, send and organize email. Lesson: Collaboration software

Encryption

Scrambling data so only someone with the right key can read it. Lesson: Compression and encryption

Establish a plan of action

How you will fix the problem, including its effects on users, such as downtime from a restart, before you carry it out. Lesson: Step 4: Plan, then implement

Ethernet

The standard way to connect devices to a wired network, using cables with RJ45 plugs. Lesson: Wired: Ethernet and fiber

Exercise equipment

Treadmills, bikes and other gym machines that upload workouts over the network. A kind of IoT. Lesson: IoT is everywhere, not just at home

ExFAT

A filesystem for flash drives that works on both Windows and macOS and allows files larger than 4 GB. Lesson: File system types

Ext4

A common filesystem on Linux computers. Lesson: File system types

External drive

A storage drive in its own case that connects by a cable, often USB, and can be unplugged and stored away. Lesson: External drives and the UPS

External flash drives

Small, portable sticks of flash memory that plug into a USB port. Non-volatile, with no moving parts. Lesson: Optical discs and flash drives

External hard drive

A hard drive in its own case that connects by a cable such as USB. It holds terabytes and can be unplugged and locked away. Lesson: Stored locally

F

FAT32

An older filesystem that works almost everywhere but cannot hold a single file larger than 4 GB. Lesson: File system types

Fiber optic

Internet service that sends data as light through glass fibers. The fastest common type, and electrical noise does not affect it. Lesson: Fiber, cable and DSL

Field

One detail stored for every record, shown as a column, like the order date. Lesson: Relational databases, tables and schema

File attributes

A simple flag on a file, such as Read-only, Hidden or Archive, that affects how it is shown or used. Lesson: Permissions, attributes and properties

File backup

A backup of the files and folders you choose, like Documents. Lesson: File backups vs. system backups

File Explorer

The Windows app for browsing drives, folders and files, and for opening a file's Properties. Lesson: System apps and utilities

File extension

The letters after the last period in a file name, like .xlsx or .pdf. They tell the OS the file type and which app opens it. Lesson: Types and extensions

File server

A computer running a server operating system that shares files over the network and can do other server jobs too. Lesson: Local network and cloud storage

File sharing

Giving others access to files, often by link. 'Anyone with the link' lets whoever gets the link open them. Lesson: Where privacy leaks

File system

The way an operating system organizes files and folders on a drive, such as NTFS, FAT32 or exFAT. Lesson: File system types

File-level encryption

Encrypting chosen files or folders, so only the allowed user can open them. Lesson: Data at rest

Firewall

A device or program that allows or blocks network traffic using rules about addresses, ports and apps. Lesson: Access points and firewalls

Firmware

Software stored in a device's chip that controls the hardware. Updating it fixes bugs and security holes. Lesson: Firmware and the BIOS

Flash drive

A small, portable stick of flash memory that plugs into a USB port. Good for carrying files and small backups. Lesson: Stored locally

Flat file

Data kept in one simple file, like a spreadsheet or CSV list. Fine for small lists that one person edits. Lesson: Flat file vs. database

Float

A number that can have a decimal part, like 12.5. Used for measured values like weight. Lesson: Every value has a type

Flowchart

A diagram of a process using shapes joined by arrows: ovals to start and end, rectangles for steps, diamonds for decisions. Lesson: Flowcharts and sequence

Folders

A container that groups files and other folders. Also called a directory. Lesson: Folders, paths and naming rules

Foreign key

A field that holds values from another table's primary key, linking the two tables. It can repeat. Lesson: Primary and foreign keys

Function

A named block of code that does one job and can be called again and again from different places. Lesson: Functions

G

Gaming console

A device built to play games on a TV with handheld controllers. Lesson: Consoles, VR and AR

General Data Protection Regulation (GDPR)

A European Union law that protects the personal data of people in the EU, even when the company is elsewhere. Lesson: PII, GDPR and cookie consent

Generative AI

AI that creates new content, such as text, images or code, from a written prompt. Lesson: Generative AI

Gigabits per second (Gbps)

About a thousand megabits per second. Fast wired networks and fiber internet run at Gbps speeds. Lesson: Throughput: bits per second

Gigabyte (GB)

About a thousand megabytes. RAM and phone storage are usually measured in gigabytes. Lesson: Bits and bytes

Gigahertz (GHz)

A billion cycles per second, or 1,000 MHz. Most PC and phone processors are rated in GHz. Lesson: Processing speed: hertz

Graphical user interface (GUI)

An interface with windows, icons and menus that you use with a mouse or touch. Lesson: GUI or command line

Graphics processing unit (GPU)

A processor built to draw images and do many simple math jobs at once, as 3D graphics and video need. Lesson: RAM and the GPU

Guest operating system (OS)

The operating system running inside a virtual machine. Lesson: Host and guest operating systems

H

Hallucination

When AI states false information, even a made-up source, as if it were fact. Lesson: Use AI wisely

Hard disk drive (HDD)

A drive that stores data magnetically on spinning platters read by a moving arm. Cheap and large, but slower and easy to damage by drops. Lesson: Hard drives and solid-state drives

Headset

Headphones with a built-in microphone, so it is both an output and an input device. Lesson: Things you type, click, scan and see with

Hertz (Hz)

One cycle per second. A processor's clock speed is counted in hertz, usually megahertz or gigahertz. Lesson: Processing speed: hertz

Hexadecimal

Base 16: digits 0 to 9, then A to F for ten to fifteen. One hex digit stands for exactly 4 bits. Used for MAC addresses and web colors. Lesson: Hexadecimal: base 16

Hidden

A file attribute that keeps a file out of normal folder views. It is not security: anyone can show hidden files. Lesson: Permissions, attributes and properties

High-Definition Multimedia Interface (HDMI)

A digital port that carries video and sound on one cable. Common on TVs, monitors and laptops. Lesson: VGA, DVI, HDMI, DisplayPort and USB-C

Home automation

A connected device that controls part of a home or building, such as a smart thermostat, lock, alarm or doorbell. Lesson: Everyday things on the network

Host

The physical computer that a hypervisor runs on and whose hardware the virtual machines share. Lesson: Host and guest operating systems

HTTPS

Secure web browsing: web traffic encrypted with TLS, usually on port 443. Plain HTTP sends data unencrypted. Lesson: Data in transit

Hybrid

Some systems on premises and some in the cloud, working together as one setup. Lesson: On premises, cloud or hybrid

Hypervisor

Software that creates and runs virtual machines and shares the physical hardware among them. Lesson: The hypervisor

I

Identifier

The name you give a variable, constant, function or object in code. Most languages ban spaces and a digit at the start. Lesson: Identifiers: variables and constants

Implement the solution

Carry out the planned fix, after the plan of action is agreed, at a time that suits the user. Lesson: Step 4: Plan, then implement

Index

An item's numbered position in an array or list. Most languages start counting at 0. Lesson: Arrays

Infinite loop

A loop that never stops because nothing inside it ever makes its condition false. Lesson: Branching and looping

Infrastructure as a Service (IaaS)

Renting virtual servers, storage and networks from a cloud provider. You install and manage the operating system and apps. Lesson: Infrastructure as a Service (IaaS)

Input

Data going into a computer, like a key press, a mouse click, a barcode scan or a voice command. Lesson: Four jobs: in, work, out, keep

Input device

Hardware that sends data into a computer, such as a keyboard, mouse, scanner, microphone or webcam. Lesson: Input and output devices

Instant messaging

Software for short, real-time text chats that often shows who is available. Lesson: Messaging, browsing and remote support

Integer

A whole number with no decimal part, positive or negative, like 42 or -7. Used for counts. Lesson: Every value has a type

Integrity

Keeping data correct, so it is changed only by people allowed to change it. Lesson: Confidentiality, integrity, availability

Interface between applications and hardware

A main job of the OS: apps ask the OS for what they need, and the OS uses drivers to work the hardware for them. Lesson: The go-between for apps and hardware

Interference

Other signals that disrupt Wi-Fi, like microwave ovens or crowded neighbor networks, mostly on 2.4 GHz. Lesson: Why signals get weak

Internet of Things (IoT)

Everyday objects with sensors or controls and a network link, like thermostats, door locks, cameras, cars and fitness trackers. Lesson: Everyday things on the network

Interpreted language

Code that runs straight from its text, with no separate build step. It needs its interpreter installed to run. Lesson: Compiled or interpreted?

Invalid certificate

A certificate the browser cannot trust, such as expired or for another site. Stop and report it instead of clicking past. Lesson: Valid and invalid certificates

IP address

A device's address on a network, given by the network, used to find and reach it. It can change when the device moves. Lesson: IP addresses, MAC addresses and ports

IP cameras

A security camera that sends video over the network using its own IP address, so it can be viewed from other devices. Lesson: IoT is everywhere, not just at home

IP-based peripheral

A device, like a network printer or camera, that joins the network itself and is reached by its IP address. Lesson: IP-based peripherals

K

Key/value database

A non-relational database that stores each value under a unique key and finds it fast by that key. Lesson: Key/value and document databases

Kilobits per second (Kbps)

About a thousand bits per second. Very old modems and alarm panels sent data at Kbps speeds. Lesson: Throughput: bits per second

Kilobyte (KB)

About a thousand bytes. A short plain-text note is a few kilobytes. Lesson: Bits and bytes

L

Laptop

A portable computer with the screen, keyboard and battery built in, for one person's work on the go. Lesson: Phones, tablets, e-readers and laptops

Least privilege

Giving each person only the access their job needs, and nothing more. Lesson: Authorization

Lightning

Apple's own small, reversible connector used on older iPhones and iPads. Lesson: Thunderbolt, Lightning, Bluetooth and RF

Local area network (LAN)

A network that covers a small area, like one home, office or building. Lesson: LAN and WAN

Looping

Repeating a set of steps until a condition is met, such as until a counter reaches a number. Lesson: Branching and looping

M

MAC address

The hardware address a maker gives a network adapter, written in hexadecimal. It normally stays the same on any network. Lesson: IP addresses, MAC addresses and ports

Machine code

The 0s and 1s a CPU runs directly. Lesson: Compiled or interpreted?

Malicious

Software built to do harm. It must be fully removed, then the device scanned. Lesson: Removing software

Malicious content

Files, links, pop-ups or apps built to do harm, like a fake virus warning or a program disguised as a PDF. Lesson: Malicious or compromised content

Markup language

A language that labels content, like headings, paragraphs and links, but does not run logic. HTML is the best-known one. Lesson: Markup languages

Meaningful reporting

Turning data into a short, clear summary, often with a chart, that people can act on quickly. Lesson: Data-driven decisions

Medical devices

Connected health devices, like glucose or heart monitors, that send readings to a phone or doctor. A kind of IoT. Lesson: IoT is everywhere, not just at home

Megabits per second (Mbps)

About a million bits per second. Home internet plans are often sold in Mbps. Divide by 8 to get megabytes per second. Lesson: Throughput: bits per second

Megabyte (MB)

About a thousand kilobytes, or about a million bytes. A phone photo is a few megabytes. Lesson: Bits and bytes

Megahertz (MHz)

A million cycles per second. Older and smaller processors, like a printer's chip, are rated in MHz. Lesson: Processing speed: hertz

Methods

A function that belongs to an object: an action it can do, like printLabel(). Lesson: Objects: properties, attributes, methods

Mirroring

Showing your whole screen on another display, exactly as you see it. Lesson: Mirroring vs. casting

Modem

A device that connects to the provider's line, like cable or DSL, and turns its signal into one your network can use. Lesson: Modem, router and switch

Monitor

A display device with its own screen that shows a computer's picture. It has no apps of its own. Lesson: Displays: monitor, smart TV, projector

Motherboard

The main circuit board (system board) that connects the CPU, RAM, storage and expansion cards so they can work together. Lesson: The motherboard and the CPU

Multifactor authentication (MFA)

Signing in with two or more different kinds of proof: something you know, something you have or something you are. Lesson: Authentication

Multiple concurrent users

Many people using the same data at the same time. Databases handle this without locking people out or losing edits. Lesson: Flat file vs. database

N

Naming restrictions

Rules for file names. Windows does not allow < > : " / \ | ? or * in a name. Lesson: Folders, paths and naming rules

Near-field communication (NFC)

Wireless that works only a few centimeters apart, used for tap-to-pay and tapping to pair. Lesson: Wireless: Bluetooth, NFC and Wi-Fi

Network interface card (NIC)

The part that connects a computer to a network. It can be wired or wireless, onboard or an expansion card. Lesson: Storage and the NIC

Network-attached storage (NAS)

A storage box on the local network that shares folders with the people on that network. Lesson: Local network and cloud storage

Non-critical data

Data whose loss causes little harm, like old drafts or party photos. Lesson: Data as an asset

Non-relational databases

A database that stores data without fixed, linked tables, such as a key/value or document database. Lesson: Key/value and document databases

Non-structured data

Data with no set fields or format, like photos, videos, audio recordings and free-form documents. Lesson: Structured, semi-structured, non-structured

Non-volatile

Keeps data with no power, like an SSD, HDD, ROM, flash drive or optical disc. Lesson: Volatile vs. non-volatile

Non-volatile memory express (NVMe)

A fast way for SSDs to talk to the computer over PCIe lanes. NVMe SSDs are much faster than SATA SSDs. Lesson: Hard drives and solid-state drives

Nonrepudiation

Proof of who did something, like a digital signature, so the person cannot later deny it. Lesson: Accounting and nonrepudiation

NTFS

The main Windows filesystem. It supports permissions, compression and encryption. Lesson: File system types

O

Object

A bundle in code that holds data about one thing (properties) together with the actions it can do (methods). Lesson: Objects: properties, attributes, methods

Object-oriented

Organizing code into objects that each keep their own data (properties) and actions (methods), often built from classes. Lesson: Comments, documentation and objects

Octal

Base 8: numbers written with the digits 0 through 7. Each place is worth eight times the one to its right. Lesson: Octal: base 8

On premises

Running systems on the company's own hardware in its own building. Lesson: On premises, cloud or hybrid

One-time purchase

Paying once for software instead of on a schedule. It usually comes with a perpetual license. Lesson: Licenses

Online workspace

One place online where a team shares chat, files, tasks and meetings. Lesson: Collaboration software

Open source

Software whose source code anyone may see, change and share, as long as they follow its license. Lesson: Licenses

Operating system (OS)

The main software that manages the hardware and gives apps a way to use it, like Windows, macOS, Linux, Android or iOS. Lesson: The go-between for apps and hardware

Optical

Discs like CDs, DVDs and Blu-ray that a laser reads and writes. Lesson: Optical discs and flash drives

Original equipment manufacturer (OEM)

The company that made the device. Its official website is the safe place to get that device's drivers and software. Lesson: Where software comes from

Output

Results coming out of a computer where people can use them, like text on a screen, a printed label or sound. Lesson: Four jobs: in, work, out, keep

Output device

Hardware that shows or delivers results from a computer, such as a monitor, printer, speakers or headset. Lesson: Input and output devices

P

Packets

A small piece of data sent across a network. Each packet carries the address of where it is going. Lesson: Packets: data in small pieces

Password complexity

Rules about which kinds of characters a password must mix: uppercase, lowercase, numbers and symbols. Lesson: Length and complexity

Password expiration

A setting that makes you change a password after a set time, like 90 days. Lesson: History, expiration and reuse

Password history

A setting that remembers your recent passwords so you cannot reuse them. Lesson: History, expiration and reuse

Password length

How many characters a password has. Length adds the most guessing work, so long passphrases are strong. Lesson: Length and complexity

Password manager

A tool that creates, stores and fills in a strong, unique password for each account behind one protected vault. Lesson: Search engine and password management

Password privacy

Keeping your password to yourself. Never share it, even with a coworker; IT can give them their own access. Lesson: Managers, privacy and resets

Password reset process

The company's set steps to change a forgotten password, which always verify who is asking first. Lesson: Managers, privacy and resets

Password reuse across sites

Using the same password on more than one site. One leak then opens every account that shares it. Lesson: History, expiration and reuse

Patching

Installing updates (patches) that fix bugs and security holes attackers already know about. Keep automatic updates on. Lesson: Securing phones and workstations

Peer-to-peer

A network model with no central server: each computer both shares and uses resources. Lesson: Client/server and peer-to-peer

Peripheral

A device that connects to a computer from outside, such as a printer, scanner, keyboard, mouse, webcam or monitor. Lesson: Things you type, click, scan and see with

Permissions

Settings that decide which users and groups may read, change or fully control a file or folder. Lesson: Permissions, attributes and properties

Perpetual

Pay once and keep using the version you bought, with no end date. Lesson: Licenses

Personally identifiable information (PII)

Information that can identify a specific person, alone or with other details, like a name with an address or a birth date. Lesson: PII, GDPR and cookie consent

Petabyte (PB)

About a thousand terabytes. Big companies and cloud providers store data in petabytes. Lesson: Bits and bytes

Phishing

A fake message that pretends to be from someone you trust to get you to click a link or give up information. Lesson: Social engineering and phishing

Plain text

Readable data before it is encrypted (or after it is decrypted). Lesson: Plain text vs. cipher text

Platform as a Service (PaaS)

A ready-made cloud platform where developers upload their own code. The provider runs the servers and operating systems. Lesson: Platform as a Service (PaaS)

Plug-and-play

The operating system notices a new device and loads its driver by itself, so it works without a manual install. Lesson: Plug-and-play vs. driver installation

Pop-up blocker

A browser setting that stops websites from opening extra windows on their own. Lesson: Cache and pop-up blockers

Port

A number that picks which service on a device gets the data, such as 443 for HTTPS or 80 for HTTP. Lesson: IP addresses, MAC addresses and ports

Pre-shared key (PSK)

One Wi-Fi passphrase shared ahead of time with everyone who may join the network. Lesson: Open vs. encrypted

Preventive measures

A step that keeps a problem from coming back, such as a charging dock for scanners that keep dying. Lesson: Step 5: Verify, then prevent

Primary key

A field whose value is unique and never empty, so it identifies exactly one row in a table. Lesson: Primary and foreign keys

Printer

An output device that puts text and images on paper or labels. Network printers have their own IP address. Lesson: Things you type, click, scan and see with

Private browsing

A browser window that does not keep its history, cookies or site data after you close it. The network can still see the sites you visit. Lesson: Private browsing

Process

A program that is running right now. Task Manager lists processes and their CPU and memory use. Lesson: Processes, services and drivers

Processing

The step where the CPU works on data by following a program's instructions, such as adding, comparing or sorting. Lesson: Four jobs: in, work, out, keep

Product keys

Codes that activate software under a license. One key covers only what its license allows, such as one PC. Lesson: Licenses

Productivity software

Apps for making your own work: word processing, spreadsheets, presentations and visual diagramming. Lesson: Productivity software

Profile synchronization

Signing in to a browser so your bookmarks, passwords and settings follow you to other devices. Lesson: Sync and bookmarks

Projector

A display device that shines a picture onto a wall or screen to make a very large image. Lesson: Displays: monitor, smart TV, projector

Prompt

The instruction or question you type into an AI tool. Lesson: Generative AI

Properties

A file's details window: its type, size, location, dates and attributes like Read-only and Hidden. Lesson: Permissions, attributes and properties

Proprietary

Software whose maker keeps the code private and limits how you may use it. Lesson: Licenses

Pseudocode

A program's logic written as plain, code-like steps for people to plan with. It is not a real language, so it cannot run. Lesson: Pseudocode

Q

Query

A request that asks a database for specific data and returns only the matching records. Lesson: What you do with a database

Query language

A language for asking a database to find, add or change data. SQL is the best-known one. Lesson: Query and assembly languages

Question the obvious

Check simple causes first, such as power, cables and settings, before you blame something costly or complicated. Lesson: Step 2: Establish a theory

R

Radio frequency (RF)

Radio waves used to send data without wires, such as a wireless mouse talking to its small USB receiver. Lesson: Thunderbolt, Lightning, Bluetooth and RF

Random-access memory (RAM)

Fast, short-term working memory that holds open programs and files. It is volatile, so it empties when power is off. Lesson: RAM and the GPU

Read-only

A file attribute that lets you open and read a file but not save changes to it. Lesson: Permissions, attributes and properties

Read-only memory (ROM)

Non-volatile memory that holds startup firmware. It is read at power-on and keeps its contents with no power. Lesson: Volatile vs. non-volatile

Record

One complete entry in a database table, shown as one row, like all of one order's details. Lesson: What you do with a database

Relational database

A database that stores structured data in tables linked by primary and foreign keys, usually managed with SQL. Lesson: Relational databases, tables and schema

Remote support software

Software that lets a helper see, and with permission control, another person's device to fix it from afar. Lesson: Messaging, browsing and remote support

Reports

A readable, formatted summary of database data, with totals or charts, that can be printed or shared. Lesson: What you do with a database

Research

Looking up an unfamiliar problem in a maker's knowledge base or online while forming a theory of probable cause. Lesson: Step 2: Establish a theory

Restoring

Copying data back from a backup. A test restore is the only way to prove a backup works. Lesson: Restoring data

RJ45

The 8-pin plug on wired Ethernet network cables. It is wider than the RJ11 plug used for phone lines. Lesson: Wired: Ethernet and fiber

Router

A device that connects different networks, such as your LAN and the internet, and forwards traffic between them by IP address. Lesson: Modem, router and switch

Row

One record in a database table: every field for one item, such as one order. Lesson: Relational databases, tables and schema

S

Satellite

Internet sent to a dish from a satellite in orbit. It reaches remote places but has delay, and storms can cut it. Lesson: Wireless: RF, satellite and cellular

Scalability

How well a system keeps working as data and use grow. Lesson: Flat file vs. database

Scanner

An input device that reads paper, photos or barcodes into the computer. Lesson: Things you type, click, scan and see with

Schema

A database's design: which tables exist, their fields and data types, and how the tables link. Lesson: Relational databases, tables and schema

Scripting languages

An interpreted language used to automate tasks and add behavior, such as Python, JavaScript or PowerShell. Lesson: Scripting languages

Secure Digital (SD) card

A small, removable flash memory card used in cameras, phones and card readers. Lesson: Stored locally

Semi-structured data

Data with labeled fields, like JSON, where the fields can change from one item to the next. Lesson: Structured, semi-structured, non-structured

Sequence

Steps running one after another, top to bottom, in the order they are written. Lesson: Flowcharts and sequence

Server

A computer that provides services, such as files, email, a database or a website, to many users over a network. Lesson: Workstations and servers

Service

A background program that can start when the computer boots and keep running with no one signed in. Lesson: Processes, services and drivers

Service set identifier (SSID)

The name a Wi-Fi network shows in the network list. It is not a secret. Lesson: Change the SSID

Single sign-on (SSO)

One sign-in that opens many apps, so you do not sign in to each one separately. Lesson: Authentication

Single-factor

Signing in with only one kind of proof, like just a password. A password plus a PIN is still single-factor. Lesson: Authentication

Small form-factor pluggable (SFP)

A slot on switches and routers that takes a swappable module, most often for fiber cable. Lesson: Wired: Ethernet and fiber

Smart TV

A TV with built-in apps and a network connection, so it can stream videos without a computer attached. Lesson: Displays: monitor, smart TV, projector

Smartphone

A pocket computer that makes calls and runs apps, with a touchscreen, cameras, GPS and a cellular connection. Lesson: Phones, tablets, e-readers and laptops

Social engineering

Tricking people, instead of hacking computers, into giving up information or access. Lesson: Social engineering and phishing

Social networking sites

Websites and apps for sharing posts, photos and messages with others. Public posts can be seen and saved by anyone. Lesson: Where privacy leaks

Software as a Service (SaaS)

A finished app that a provider runs and updates. You just sign in and use it, often in a web browser. Lesson: Software as a Service (SaaS)

Software piracy

Copying, sharing or using software without a valid license, such as a cracked copy. Pirated copies often hide malware. Lesson: Where software comes from

Solid-state drive (SSD)

A drive that stores data on flash chips with no moving parts, so it is faster and handles bumps better than an HDD. Lesson: Hard drives and solid-state drives

Speakers

Output devices that play sound from the computer. Lesson: Things you type, click, scan and see with

Spreadsheet

Software that keeps numbers in cells and uses formulas that recalculate when a value changes. Lesson: Productivity software

Storage

Keeping data so it is still there later, even after the power goes off, like a file saved to a drive. Lesson: Four jobs: in, work, out, keep

Streaming media devices

A small box or stick that plugs into a TV and plays shows, movies and music streamed from the internet. Lesson: IoT is everywhere, not just at home

String

A data type that holds text: a sequence of characters, like a product name. Digits in quotes are a string too. Lesson: Every value has a type

Structured data

Data that follows a fixed layout, so every entry has the same fields, like rows in a table. Lesson: Structured, semi-structured, non-structured

Subscription

A license paid on a schedule, like monthly. Access stops when the payments stop. Lesson: Licenses

Switch

A device that connects wired devices within one local network and sends data out the port toward the right device. Lesson: Modem, router and switch

System applications and utilities

A small built-in program for looking after the system, such as Task Manager or Disk Management. Lesson: System apps and utilities

System backup

A backup of a whole computer: operating system, apps, settings and files, so it can be rebuilt as it was. Lesson: File backups vs. system backups

T

Tables

Grids of data about one kind of thing, with rows (records) and columns (fields). Relational databases link tables by keys. Lesson: Relational databases, tables and schema

Tablet

A handheld general-purpose computer with a large touchscreen that runs apps, takes photos and joins video calls. Lesson: Phones, tablets, e-readers and laptops

Task Manager

A Windows utility that shows running apps and processes, how much CPU and memory they use, and lets you end a stuck one. Lesson: System apps and utilities

Terabits per second (Tbps)

About a thousand gigabits per second. Only the biggest network backbones move data this fast. Lesson: Throughput: bits per second

Terabyte (TB)

About a thousand gigabytes. Many hard drives and backup drives hold one or more terabytes. Lesson: Bits and bytes

Third-party

A site run by someone other than the maker. Downloads there can be outdated, bundled with extras or tampered with. Lesson: Where software comes from

Throughput

How much data moves in a set amount of time, usually counted in bits per second (bps, Kbps, Mbps, Gbps, Tbps). Lesson: Throughput: bits per second

Thunderbolt

A fast connection that uses the USB-C shape and is marked with a lightning-bolt icon. It still accepts USB-C devices. Lesson: Thunderbolt, Lightning, Bluetooth and RF

Troubleshooting methodology

A step-by-step way to fix problems: identify, form a theory, test it, plan and fix, verify, then document. Lesson: A plan for any problem

U

Uninterruptible power supply (UPS)

A box with a battery inside that keeps devices running for a short time when the power fails or flickers. Lesson: External drives and the UPS

Unnecessary

Software that is not needed, like an unused trial. Removing it saves space and leaves less to attack. Lesson: Removing software

Unwanted

Software you did not mean to install, often bundled with something else, like an ad-showing toolbar. Lesson: Removing software

USB lock

A small physical blocker that covers a USB port so no one can plug in an unknown device. Lesson: Securing phones and workstations

USB-A

The flat, rectangular USB plug found on computers and chargers. Lesson: USB-A, USB-B and USB-C

USB-B

The squarish USB plug found on devices like printers. Lesson: USB-A, USB-B and USB-C

USB-C

A small, oval, reversible plug. It can carry data, power and, on ports that support it, video. Lesson: USB-A, USB-B and USB-C

V

Valid certificate

A certificate the browser trusts, shown with a padlock. It proves the site's identity, not that the site is honest. Lesson: Valid and invalid certificates

Variable

A named place that stores a value the program can change while it runs. Lesson: Identifiers: variables and constants

Vehicles

Cars and trucks with a network link that get updates, share location and can call for help. A kind of IoT. Lesson: IoT is everywhere, not just at home

Video Graphics Array (VGA)

An old analog video port with a blue 15-pin connector. It carries no sound. Lesson: VGA, DVI, HDMI, DisplayPort and USB-C

Virtual machine (VM)

A software computer that runs on a physical host and has its own operating system, called the guest OS. Lesson: One computer, many machines

Virtual reality (VR)

A headset that blocks out the real world and shows a world made fully by the computer. Lesson: Consoles, VR and AR

Virtualization

Running several virtual computers on one physical computer, each sharing its hardware. Lesson: One computer, many machines

Visual diagramming

Software with shapes and connectors for flowcharts, network maps and floor plans. Lesson: Productivity software

Volatile

Needs power to keep data. RAM is volatile, so unsaved work is lost when the power goes off. Lesson: Volatile vs. non-volatile

VPN

An encrypted tunnel from a device to another network, like the company network, that protects data on public Wi-Fi. Lesson: Data in transit

W

Wearable devices

A small computer you wear, such as a smartwatch or fitness tracker, that collects data like steps or heart rate. Lesson: IoT is everywhere, not just at home

Web camera

A camera that sends video into the computer for calls and recordings. It is an input device. Lesson: Things you type, click, scan and see with

Web-based configuration

Setting up a network device by typing its IP address into a web browser to open its built-in settings page. Lesson: Web-based configuration

Web-browsing software

Software that requests web pages and shows them, such as when shoppers open an online store. Lesson: Messaging, browsing and remote support

Wi-Fi 6E

Wi-Fi 6 (802.11ax) extended to the 6 GHz band. Only Wi-Fi 6E and newer devices can use 6 GHz. Lesson: 802.11n, ac and ax

Wi-Fi Protected Access (WPA)

The first version of Wi-Fi Protected Access security. It is outdated and weak today. Lesson: WPA, WPA2 and WPA3

Wide area network (WAN)

A network that links networks across long distances, such as company sites in different towns. The internet is the biggest WAN. Lesson: LAN and WAN

Word processing

Software for writing formatted documents with headings, page numbers and tables of contents. Lesson: Productivity software

Workstation

A powerful computer that one person uses at a desk for heavy work like design, 3D models or video editing. Lesson: Workstations and servers

WPA2

The Wi-Fi security standard that replaced WPA. Still acceptable when an older device needs it. Lesson: WPA, WPA2 and WPA3

WPA2/WPA3 transition mode

A Wi-Fi setting that lets WPA3 devices use WPA3 while older devices join with WPA2. Lesson: WPA, WPA2 and WPA3

WPA3

The newest and strongest Wi-Fi security standard, with better protection against password guessing. Lesson: WPA, WPA2 and WPA3

Acronyms

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