JavaScript
The language of the web. Make things happen — runs right in your browser.
javascript 15 Lessons
Every lesson runs in your browser — write real code, press Run, and the tasks check themselves. Free, no account needed, with notes in English and Chinese.
Lessons in this course
- history A short history of JavaScript
- usage What JavaScript is used for
- resources Where to learn more
- setup Run JavaScript anywhere
- 01 console.log and comments
- 02 Variables — let and const
- 03 Numbers and maths
- 04 Strings
- 05 Template literals
- 06 Booleans and comparisons
- 07 if / else
- 08 for loops
- 09 while loops
- 10 Functions
- 11 Arrow functions
- 12 Arrays
- 13 Array methods
- 14 Objects
- 15 Putting it together