JavaScript is what makes a page interactive — reacting to clicks, updating content without a reload, and talking to servers behind the scenes. This module covers the language itself first (variables, functions, control flow, arrays and objects), then moves into the browser-specific parts: the DOM, events, and asynchronous programming.
This is a bigger module than the last two, so it has more lessons than usual — work through them at your own pace, then move on to Web APIs once you're comfortable with the core language.
Declaring variables with let/const, JavaScript's core data types, and the operators you'll use constantly.
Declaring and calling functions, arrow function syntax, and how scope decides what a variable can see.
Branching logic with if/else and switch, and repeating work with for, while, and array-friendly loops.
Working with lists of data using map, filter, reduce, and the other array methods you'll reach for daily.
thisStructuring data with objects, accessing properties and methods, and how this behaves in different contexts.
Selecting elements, changing content and styles, and creating or removing nodes from a live page.
Responding to clicks, input, and other user actions, plus event bubbling and delegation.
Why JavaScript is asynchronous, and the three patterns you'll see for handling things that take time.
Destructuring, template literals, spread/rest, and modules — the modern syntax you'll see in most codebases.
A written reference covering the module's syntax and patterns — good for a quick lookup after watching the videos.
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