An introduction to writing JavaScript

Lesson 1 · On the house

You, the browser, and console.log

What JavaScript is, and the first line that talks back.

Lesson 2

Let, const, and numbers

Bind names; prefer const until you must reassign.

Lesson 3

Strings and template literals

Quotes, concatenation, and templates.

Lesson 4

Booleans and comparisons

true, false, ===, and careful ==.

Lesson 5

If and else

Branches that choose a path.

Lesson 6

While and for

Repeat until done.

Lesson 7

Arrays

Ordered lists with .push and indexing.

Lesson 8

Objects

Named fields with braces.

Lesson 9

Functions

Name a block of work.

Lesson 10

A small program

Compose log, names, and a loop.