Glossary

JavaScript

Definition: JavaScript is the programming language of the web, enabling interactive and dynamic behaviour in browsers and server-side applications via Node.js.

JavaScript is a high-level, interpreted programming language originally created for web browsers. Together with HTML and CSS, it forms the triad of core web technologies. JavaScript enables interactive elements — form validation, animations, dynamic content loading, single-page applications — without a full page reload.

Client-Side vs Server-Side

  • Client-side JS — Runs in the user's browser. Manipulates the DOM, handles events, calls APIs.
  • Server-side JS — Runs on a server via Node.js. Handles routing, database queries, business logic.

Modern JavaScript (ES6+)

  • let / const — Block-scoped variable declarations.
  • Arrow functions — const add = (a, b) => a + b;
  • Promises & async/await — Cleaner asynchronous code.
  • Modules — import / export for code organisation.
  • Template literals — `Hello, ${name}!`
  • Destructuring — const { id, name } = user;

Popular Frameworks

  • React — UI component library by Meta.
  • Vue — Progressive framework for building UIs.
  • Angular — Full-featured framework by Google.
  • Next.js — React framework with SSR and static generation.
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