Introduction to JavaScript — What is JavaScript? — History and evolution — JavaScript in browsers — JavaScript vs ECMAScript Setting Up Environment — Writing JS in HTML (script tag) — Developer tools in browsers — External vs inline scripts Variables & Data Types — `var`, `let`, and `const` — Primitive data types — Type coercion and conversion — `typeof` operator Operators — Arithmetic, assignment, comparison — Logical, bitwise, and ternary — Nullish coalescing and optional chaining Control Flow — `if`, `else`, `switch` — `while`, `do...while`, `for` — `break`, `continue`, and labels Functions — Function declaration & expression — Parameters & return values — Arrow functions — IIFE (Immediately Invoked Function Expression) Arrays — Creating and accessing arrays — Array methods (`push`, `pop`, etc.) — Iterating arrays (`for`, `forEach`, `map`) — Multidimensional arrays Objects — Object literals and properties — Dot vs bracket notation — `this` keyword — Object methods and nested objects Strings — String creation and properties — Common methods (`slice`, `split`, etc.) — Template literals DOM Manipulation — `document.querySelector`, `getElementById`, etc. — Modifying elements and styles — Creating and removing elements — Event listeners Events — Event types (click, input, submit) — Event bubbling and delegation — `preventDefault` and `stopPropagation` Error Handling — `try`, `catch`, `finally` — `throw` statement — Custom errors Dates and Times — `Date` object — Formatting and parsing dates — Time calculations Timers — `setTimeout` and `setInterval` — Clearing timers Scope & Hoisting — Global vs local scope — Lexical scope — Hoisting behavior Closures — Understanding closures — Use cases (data hiding, factories) JavaScript in Browser — `window`, `document`, and `navigator` — `alert`, `prompt`, and `confirm` — Cookies and localStorage/sessionStorage Asynchronous JavaScript — Callbacks — Promises — `async` / `await` Fetch API & AJAX — Making HTTP requests — Fetch with `then`/`catch` — Error handling and JSON parsing ES6+ Features — Destructuring — Spread and rest operators — Default parameters — `for...of`, `map`, `set` Modules — `import` / `export` — Module bundlers (Webpack, Parcel) — Script `type='module'` Classes and OOP — Class syntax — Inheritance — Encapsulation — Static and private fields Regular Expressions — Regex syntax and flags — Matching, replacing, testing — Common use cases Functional Programming — Pure functions — Immutability — Higher-order functions — `map`, `filter`, `reduce` Memory Management — Garbage collection — Memory leaks and optimization Event Loop and Concurrency — Call stack — Event loop and task queues — Microtasks vs macrotasks Web APIs — Geolocation, Notifications, Clipboard — Speech recognition and camera APIs Debugging and Tools — Console methods — Breakpoints and watch — Source maps Security in JavaScript — XSS and CSP — Secure coding practices JavaScript Design Patterns — Module, Singleton, Factory, Observer — MVC and MVVM