Lesson 17 of 30

JavaScript basics

JavaScript makes pages interactive. Declare variables with const (won't be reassigned) or let (will be). Open the browser console with F12 to experiment.

Key points

const by default, let when it changes
console.log() prints to the console
Avoid var in new code

const name = "Lazo";
let score = 0;
score += 10;
console.log(name, score);

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Quiz · +10 XP

JavaScript basics

Key points

Which keyword declares a variable you won't reassign?