Why These Terms Keep Coming Up
You've seen the pop-up asking about cookies. You've been told to try a VPN. Your router settings mention something called DNS. These aren't niche tech topics — they're the everyday language of the internet, and understanding them puts you in control of your own online experience.
This reference covers the terms that appear most often in everyday computer use, browser settings, and online privacy conversations. No prior technical knowledge needed. For a broader foundation, see our introduction to computers and the internet.
| What DNS stands for | Domain Name System |
| What the padlock icon means | The page uses HTTPS (encrypted connection) |
| What a cookie stores | Small data files: login state, preferences, tracking info |
| VPN primary function | Encrypts traffic and masks your IP address |
| Latency measured in | Milliseconds (ms) |
| 2FA second factor type | Usually a one-time code sent to your phone or generated by an app |
Core Internet & Networking Terms
These are the building blocks of how data moves between your device and the rest of the web.
IP Address
Every device connected to the internet is assigned an IP address (Internet Protocol address) — a unique numerical label, like a mailing address, that identifies your device on a network. Your home network has one public IP address shared by all devices in the house, plus private addresses assigned internally to each device by your router.
DNS (Domain Name System)
DNS acts as the internet's phone book. When you type a web address like example.com, your device contacts a DNS server to translate that human-readable name into the numerical IP address of the website's server. Without DNS, you'd need to memorize long strings of numbers to visit any website. Learn more about how this works in our article on what your browser does when you visit a website.
Bandwidth and Latency
Bandwidth is the maximum amount of data your connection can transfer at once — often described in Mbps (megabits per second). Latency is the delay between sending a request and receiving a response, measured in milliseconds. High bandwidth matters for downloading large files; low latency matters for video calls and gaming. For a deeper look, see what your internet speed numbers actually mean.
IP Address
A unique numerical label assigned to every device on a network. It allows data to be routed to the correct destination, similar to a postal address for internet traffic.
DNS
Domain Name System. A service that translates human-readable web addresses (like example.com) into the numerical IP addresses computers actually use to locate servers.
VPN
Virtual Private Network. An encrypted connection that routes your internet traffic through a remote server, masking your IP address and protecting data on unsecured networks.
Cookie
A small data file stored on your device by a website. Cookies can remember login status, preferences, and browsing behavior. First-party cookies are set by the site you visit; third-party cookies are set by outside services embedded on the page.
Firewall
A security system — either hardware or software — that monitors and filters network traffic based on predefined rules, blocking unauthorized connections.
HTTPS
HyperText Transfer Protocol Secure. The encrypted version of HTTP, used to protect data exchanged between your browser and a website. Indicated by a padlock icon in the address bar.
Bandwidth
The maximum data transfer capacity of a network connection, typically measured in megabits per second (Mbps). Higher bandwidth generally means faster downloads and smoother streaming.
Cache
Temporarily stored data — such as images and scripts from websites — saved locally so pages load faster on repeat visits. Clearing the cache can resolve display errors.
Two-Factor Authentication (2FA)
A security method requiring two forms of identity verification — typically a password plus a one-time code — before granting access to an account.
Encryption
The process of encoding data so it can only be read by someone with the correct decryption key. Widely used to protect passwords, financial data, and messages in transit.
Phishing
A type of social engineering attack where an attacker impersonates a trusted entity to trick a user into revealing sensitive information such as passwords or payment details.
Firmware
Permanent low-level software embedded in hardware devices like routers, printers, and smart TVs. Firmware updates can improve performance and fix security vulnerabilities.
Privacy & Security Terms
These terms come up whenever you're managing your privacy, protecting your accounts, or reading about online threats.
Cookies
A cookie is a small file a website stores on your device to remember information about you — like that you're logged in, what's in your shopping cart, or your preferences. First-party cookies are set by the site you're visiting; third-party cookies are set by advertisers or trackers embedded on that page. Browsers now give you increasing control over which cookies to allow.
VPN (Virtual Private Network)
A VPN creates an encrypted tunnel between your device and a server operated by the VPN provider. Your internet traffic is routed through that server, masking your real IP address and making your connection harder to intercept on public Wi-Fi. A VPN doesn't make you invisible online — it shifts where your browsing data goes, not whether it exists. Our article on your digital footprint explains what data you generate regardless of a VPN.
Firewall
A firewall monitors incoming and outgoing network traffic and blocks connections that don't meet defined security rules. Your operating system almost certainly has a built-in software firewall; your router provides a hardware-level firewall between your home network and the public internet.
Encryption
Encryption scrambles data so that only someone with the correct key can read it. The padlock icon in your browser's address bar indicates an HTTPS connection — meaning data between your browser and the website is encrypted in transit. This protects passwords and payment information from being read if intercepted.
HTTP vs. HTTPS: The Practical Difference
HTTP (without the S) transmits data without encryption, meaning it could theoretically be intercepted. HTTPS encrypts the connection. Most modern browsers now flag HTTP-only sites as 'Not Secure.' You don't need to do anything special to use HTTPS — if a site supports it, your browser will use it automatically.
Two-Factor Authentication (2FA)
Two-factor authentication adds a second verification step beyond your password — typically a code sent to your phone or generated by an app. Even if someone obtains your password, they can't access your account without the second factor.
Phishing
Phishing is a type of scam where attackers impersonate a trusted source — a bank, a delivery company, a tech provider — to trick you into handing over login credentials or financial information. It most often arrives by email but also occurs via text message (sometimes called smishing) or phone call.
Software & Device Terms Worth Knowing
These terms appear frequently in device settings, update notifications, and tech support conversations.
Operating System (OS)
The operating system is the core software that manages your device's hardware and lets applications run on top of it. Windows, macOS, iOS, and Android are all operating systems.
Cache
A cache is a stored collection of data — images, scripts, page elements — that your browser or app saves locally so it doesn't have to re-download the same content every visit. Clearing your cache can fix display problems with websites and free up storage space.
Software Update vs. Firmware Update
A software update changes the programs running on your device, including your OS and apps. A firmware update updates the low-level programming built into a hardware device — like your router, smart TV, or printer. Both types of updates often include security patches and are generally worth applying promptly. See how to keep a home computer running smoothly for practical maintenance habits.
Understanding how your hardware components interact with all this software is also useful — our guide to RAM, storage, and processing power covers the essentials.
80%+
Web traffic using HTTPS encryption
According to Google's Transparency Report, the majority of pages loaded in Chrome use HTTPS, a significant increase over the past decade.
3.4 billion
Phishing emails sent daily (estimated)
Industry security researchers estimate billions of phishing messages are sent each day, making it one of the most common cybersecurity threats consumers face.
The content on this site is for informational purposes only and is not a substitute for professional advice. Always consult a qualified professional for guidance specific to your situation.