JavaScript: free course

Make pages interactive: variables, functions, arrays, objects, loops, the DOM and events.

21 lessons · free · no account needed · code examples, practice questions and videos

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Lessons

1. 1 JavaScript introduction: what it is, why we need it, who uses it and your first programs
2. 2 Variables and data types
3. 3 Strings, numbers and operators
4. 4 Numbers, Math and dates: money, rounding, random numbers and time
5. 5 Conditions: if, else, comparison, logical operators, switch and the ternary operator
6. 6 Arrays and loops: storing lists of data and repeating actions
7. 7 Array methods: map, filter, reduce, find and sort
8. 8 Functions and objects: reusable code and structured data
9. 9 Objects in depth: destructuring, spread and JSON
10. 10 Scope, hoisting and closures
11. 11 Errors, try/catch and debugging
12. 12 The DOM and events: changing the page and responding to clicks, typing and more
13. 13 Handling forms and validating input
14. 14 Regular expressions: validating phone numbers, emails, KRA PINs and searching text
15. 15 JSON and fetch: exchanging data with servers and APIs
16. 16 Promises and async/await: handling things that take time
17. 17 Saving data in the browser: localStorage, sessionStorage, cookies and IndexedDB
18. 18 Classes and object-oriented JavaScript
19. 19 Modules, npm and the modern JavaScript toolbox
20. 20 Project: build a complete to-do list app, step by step
21. 21 Project: a quiz app with score and timer