Tech Glossary
Plain-English definitions of the terms that developers and curious users end up searching for: APIs, webhooks, CORS, DNS, encryption, OAuth, and more. Each entry is short enough to read in under two minutes and links to the Utilko tools you'd actually use when working with that concept.
What Is an API? Plain-English Explanation + Examples
An API (Application Programming Interface) is a defined way for one piece of software to ask another for data or work. Clear explanation with REST, GraphQL, and public API examples.
What Is a CDN? Why Websites Load Fast Everywhere
A CDN (Content Delivery Network) is a global network of servers that caches your website's assets close to users. Explanation of edge caching, pop locations, and why it matters.
What Is CORS? The Browser Security Rule, Explained
CORS (Cross-Origin Resource Sharing) is how browsers decide whether a web page can call an API at a different origin. Plain explanation of origins, preflights, and how to fix common CORS errors.
What Is DNS? How Your Browser Finds Websites
DNS (Domain Name System) is the global lookup service that converts domain names like utilko.com into IP addresses your computer can connect to. Clear explanation of records, recursion, and caching.
What Is Encryption? Symmetric, Asymmetric, and When to Use Each
Encryption scrambles data so only someone with the key can read it. Clear explanation of symmetric (AES) and asymmetric (RSA) encryption, hashing, and common real uses.
What Is an HTTP Cookie? How Web Sessions Actually Work
A cookie is a small piece of data a website stores in your browser that gets sent back with every subsequent request. Explanation of session cookies, flags, and third-party cookies.
What Is an IP Address? Public vs Private, IPv4 vs IPv6
An IP address is the unique identifier assigned to any device on a network — how the internet knows where to send data. Clear explanation of IPv4, IPv6, public vs private, and static vs dynamic.
What Is OAuth? How "Sign In With Google" Actually Works
OAuth is the industry-standard protocol that lets you grant one app limited access to your data on another, without giving it your password. Clear walkthrough of OAuth 2.0 flows.
What Is a Webhook? Clear Explanation + When to Use One
A webhook is a reverse API: instead of you calling a server, the server calls your URL when something happens. Plain-English explanation with examples and security tips.
What Is a WebSocket? Real-Time Two-Way Web Connections
A WebSocket is a persistent two-way connection between browser and server that stays open for instant messaging, live updates, and multiplayer features. Clear explanation with use cases.
Want to try the concepts?
Every glossary entry links to the Utilko tools that let you experiment with the concept — generate a UUID, decode a JWT, hash a string, look up an IP.
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