Web Development · Glossary · Beginner Friendly
Web Development Glossary: Key Words Explained Simply
Quick summary — why a web development glossary helps
You don't need to memorise everything — you just need to recognise the words. When you read tutorials or job descriptions, unfamiliar terms make everything feel harder than it is. This glossary covers the essential vocabulary in plain English so you can follow along.
In this guide you will find:
- HTML & CSS terms — structure and styling essentials.
- JavaScript terms — behaviour and interactivity.
- Backend & API terms — servers and data.
- Dev tools & workflow terms — Git, builds, deployment.
- How to use the glossary — practical tips for learning.
SECTION 01HTML & CSS terms
HTML and CSS define how a page is structured and how it looks. Here are the essential terms.
| Term | Plain English meaning |
|---|---|
| HTML | The structure of a page — headings, paragraphs, links |
| Tag | Labels in angle brackets that define content (like <p>) |
| Element | An opening tag, content, and closing tag together |
| Attribute | Extra information on a tag (like href on a link) |
| CSS | Rules that style HTML — colours, layout, fonts |
| Selector | The part of CSS that picks which element to style |
| Class | A reusable label used to style multiple elements |
| Flexbox | A layout system for arranging items in rows or columns |
| Grid | A layout system for two-dimensional layouts |
| Responsive design | Making pages adapt to phones, tablets, and desktops |
| Media query | CSS rules that apply based on screen size |
SECTION 02JavaScript terms
JavaScript makes pages interactive. These terms appear in almost every tutorial.
| Term | Plain English meaning |
|---|---|
| Variable | A named box that stores a value |
| Function | A reusable block of code that does something |
| Array | An ordered list of values (like [1, 2, 3]) |
| Object | A collection of key-value pairs ({ name: "A" }) |
| DOM | The Document Object Model — the page as a tree you can change |
| Event | Something that happens (like a click or keypress) |
| Callback | A function passed into another function to be called later |
| Promise | A value that will arrive later (e.g., an API result) |
| async / await | A cleaner way to write code that waits for results |
| Fetch | A built-in function to make HTTP requests |
| Framework | A toolkit built on top of JS (React, Vue, Angular) |
SECTION 03Backend & API terms
Backend terms describe how the data and logic behind a page work.
| Term | Plain English meaning |
|---|---|
| Server | A computer that responds to requests from browsers |
| Client | The browser or app that makes requests |
| API | A defined way to request data or actions from a server |
| REST | A common style of API design using URLs and HTTP verbs |
| Endpoint | A specific URL where an API accepts requests |
| JSON | A common data format that looks like JavaScript objects |
| Database | Where data is stored and retrieved |
| SQL | A language for querying relational databases |
| Authentication | Proving who you are (login) |
| Authorisation | What you are allowed to do after logging in |
| Token | A short string passed to the server to identify you |
# Making a simple API request with fetch
fetch("https://api.example.com/users/1")
.then(response => response.json())
.then(data => {
console.log("User name:", data.name);
});
# In plain English:
# "Go to this URL, get the data,
# convert it to JSON,
# then print the user's name."// A typical JSON response looks like this:
{
"id": 1,
"name": "Ananya",
"role": "developer",
"skills": ["HTML", "CSS", "JavaScript"]
}
// JSON is just a text format for structured data.
// It looks like a JavaScript object,
// but it can be used by any language.SECTION 04Dev tools & workflow terms
These terms appear on job listings, GitHub, and deployment platforms. They describe how code is written, shared, and shipped.
| Term | Plain English meaning |
|---|---|
| Git | A tool that tracks changes in your code |
| Repository (repo) | A project folder tracked by Git |
| Commit | A saved snapshot of changes |
| Branch | A parallel version of the code for new work |
| Merge | Combining changes from one branch into another |
| Pull request | A request to merge your changes, usually after review |
| CI/CD | Automated testing and deployment pipelines |
| Deployment | Putting your code on a server so people can use it |
| Hosting | The service that serves your site to visitors |
| Domain | Your website's name (like example.com) |
| Build | Preparing your code for production (bundling, minifying) |
SECTION 05How to use this glossary
A glossary is a tool, not a study plan. Here is how to use it effectively.
- Return to it as you read — check a term once, keep reading, and come back when it appears again.
- Don't memorise — recognise — you'll naturally learn by using these terms in real work.
- Keep it open while coding — a quick refresh is often enough to unblock you.
- Add your own terms — whenever you encounter a new word, write it down with your own explanation.
- Build a small project — the fastest way to make terms stick is to use them.
SECTION 06Interview Q&A — web development terms
Q1What's the difference between HTML and CSS?
HTML defines the structure and content of a page. CSS defines its appearance — colours, spacing, layout, and fonts.
Q2What is the DOM in simple terms?
The DOM is the page as a tree of elements that JavaScript can read and change. When you click a button and something updates on the page, JavaScript is manipulating the DOM.
Q3What's the difference between an API and a database?
A database stores data. An API defines how to access or change that data from the outside. The API is the doorway, the database is the room behind it.
Q4Why do developers use Git?
Git tracks changes to code so developers can collaborate, work on separate branches, and roll back if something breaks. It's the standard for version control in web development.
Q5What does "responsive design" mean?
Responsive design means the page adjusts to different screen sizes — from phones to desktops — using CSS techniques like flexible layouts and media queries.
SECTION 07Test yourself — web development glossary quiz
Five questions. No sign-up.
0 / 5Pick an answer to see why it is right or wrong.
SECTION 08Frequently asked questions
What's the difference between HTML and CSS?
HTML provides structure and content; CSS provides appearance. Together they define how a page looks and reads.
What is an API in plain English?
An API is a way for one program to ask another for data or actions, using a defined set of requests.
What's the difference between Git and GitHub?
Git tracks changes to code on your computer. GitHub is a website that hosts Git repositories online for sharing and collaboration.
What is JSON and why is it used?
JSON is a lightweight text format for structured data. It's used because it's easy to read, easy to parse, and works across languages.
Do I need to memorise all these terms?
No. Recognising them is enough. You'll naturally memorise the ones you use. The glossary is a reference, not a test.
SECTION 09Related reads
Classroom & online · Noida
Learn the words, then learn the work
Our Full-Stack Web Development Course teaches HTML, CSS, JavaScript, APIs, Git, and deployment — with real projects so the vocabulary sticks.
₹15,500 · full programme- Beginner-friendly curriculum
- Project-based learning
- Mock interviews
- Weekday & weekend batches