Glossary
Plain English definitions — no jargon, just clear explanations.
INFO
- Type: Reference
- Usage: Look up terms as you encounter them
Core Web Terms
| Term | Plain English |
|---|---|
| API | A way for programs to talk to each other over the internet |
| Backend | Code that runs on a server (hidden from users) |
| Frontend | Code that runs in the browser (what users see) |
| Server | A computer that serves content to other computers |
| Client | The program (usually a browser) that requests content from a server |
| HTTP/HTTPS | The protocol browsers use to talk to servers (S = secure) |
| URL | Web address (Uniform Resource Locator) |
| DNS | The system that turns domain names into server addresses |
| SSL/TLS | The encryption that makes HTTPS secure |
Development Terms
| Term | Plain English |
|---|---|
| CLI | Command Line Interface - a text-based way to use programs |
| IDE | Integrated Development Environment - a fancy text editor for code (like VS Code) |
| Terminal | The text-based interface where you type commands |
| Package | Code other people wrote that you can use in your project |
| Dependency | A package your project needs to work |
| npm | Node Package Manager - installs JavaScript libraries |
| Localhost | Your own computer, when running a server |
| DevTools | Browser Developer Tools - built-in debugging panel (press F12) |
| Console | Part of DevTools showing errors, warnings, and log messages |
| Stack trace | A breadcrumb trail showing the path code took to reach an error |
File & Data Terms
| Term | Plain English |
|---|---|
| JSON | A format for structured data (like a form with fields) |
| Markdown | Simple text formatting (used for documentation, READMEs) |
| Environment Variable | A setting stored outside your code (often secrets) |
| .env file | A file that stores environment variables |
| Payload | The data being sent in a request or message |
| VCard/VCF | A standard format for contact information (name, email, phone) |
Version Control Terms
| Term | Plain English |
|---|---|
| Git | A tool that tracks changes to your code over time |
| GitHub | A website that hosts Git repositories |
| Repository (repo) | A project folder tracked by Git |
| Commit | A snapshot of your project at a specific moment |
| Branch | A parallel version of your code |
| Merge | Combining two branches together |
| Push | Upload your commits to GitHub |
| Pull | Download commits from GitHub |
| Clone | Copy a repository from GitHub to your computer |
| Pull Request (PR) | A request to merge your changes into another branch |
Deployment Terms
| Term | Plain English |
|---|---|
| Deploy | Put your code on the internet so others can access it |
| Hosting | A service that runs your code on their servers |
| Static site | A website with files that don't change per user |
| Dynamic site | A website that generates different content per user |
| CDN | Content Delivery Network - serves your site from locations near users |
| CI/CD | Continuous Integration/Deployment - automatic testing and deploying |
| Build | Converting your source code into files ready for deployment |
Security Terms
| Term | Plain English |
|---|---|
| API Key | A password for programs (not humans) |
| Token | A piece of text that proves who you are to an API |
| OAuth | A way to log in using another service (like "Login with Google") |
| JWT | JSON Web Token - an encoded identity card for APIs |
| CORS | Cross-Origin Resource Sharing - browser security that blocks some requests |
| Rate limiting | Restricting how many requests can be made in a time period |
| Circuit breaker | A pattern that stops making requests when errors spike |
AI Terms
| Term | Plain English |
|---|---|
| LLM | Large Language Model - AI trained on text to predict words |
| Token | Roughly a word piece (used to measure AI input/output) |
| Context window | How much text AI can "remember" in one conversation |
| Hallucination | When AI confidently makes something up |
| Prompt | The text you send to AI |
| Agent | AI that can take actions (not just answer questions) |
| MCP | Model Context Protocol - lets AI connect to external data |
| Exponential backoff | Waiting longer between retries after each failure (1s, 2s, 4s, 8s...) |
Framework Terms
| Term | Plain English |
|---|---|
| Framework | Pre-written code that gives you a structure to build on |
| Library | Code you can use, but doesn't dictate structure |
| React | A JavaScript library for building user interfaces |
| Next.js | A framework built on React for full websites |
| Node.js | JavaScript that runs outside the browser (on servers) |
Common Abbreviations
| Abbreviation | Meaning |
|---|---|
| API | Application Programming Interface |
| CSS | Cascading Style Sheets |
| HTML | HyperText Markup Language |
| JS | JavaScript |
| JSON | JavaScript Object Notation |
| REST | Representational State Transfer |
| URL | Uniform Resource Locator |
| UI | User Interface |
| UX | User Experience |