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JavaScript

JavaScript Fundamentals

Programming logic, the DOM, events, and asynchronous data in the browser.

beginner9 lessons4 modules7h total

Helpful before you begin (optional -- you can start this course now): HTML & CSS Fundamentals

Who it's for

Learners comfortable with HTML and CSS who want to make pages respond to input and load real data.

What you'll be able to do

  • Write functions, loops, and conditionals that solve a stated problem
  • Model data with arrays and objects and transform it without mutating by accident
  • Read and update the DOM in response to user events
  • Fetch remote data and handle both success and failure paths

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Language basics

Values, decisions, and repetition.

  1. Variables and Data Types

    Store and label values with let and const, and meet JavaScript's basic types.

    20 min

  2. Operators and Conditionals

    Compare values and branch your program's logic with if/else.

    22 min

  3. Loops

    Repeat work with for and while loops, and control them with break and continue.

    22 min

Structuring code and data

Reusable logic and the two collection types you will use constantly.

  1. Functions

    Package reusable logic into named functions with parameters and return values.

    24 min

  2. Arrays and Objects

    Group related values in arrays and objects, and transform them with array methods.

    26 min

Working with the browser

Reading, changing, and reacting to the page.

  1. DOM Selection and Updates

    Find elements on a page with JavaScript and change what they show.

    24 min

  2. Events and Forms

    Respond to clicks and form submissions, and read what a user typed.

    24 min

Asynchronous JavaScript

Code that waits, and code that handles failure.

  1. Modules and Async Programming Fundamentals

    Organize code across files with import/export, and handle time-delayed work with Promises.

    26 min

  2. Fetch and Error Handling

    Request data with the Fetch API and handle both success and failure paths.

    26 min

Where to go next

Optional -- these build well on what you just learned, but any course can come next.

TypeScript Foundations

Add a type system to JavaScript: catch mistakes while you write, and model data so wrong states cannot be represented.

Git, APIs & SQL

Collaborate with version control, consume APIs, and query relational data.