Modern JavaScript Foundations
A friendly, practical introduction to modern JavaScript — variables, functions, arrays and the syntax you'll use every day.
View courseSkill Level
Beginner
Language
Declaring Variables with let and const
When to use let, when to use const, and why var is best left behind.
Read tutorialFunctions and Arrow Syntax
Write functions the classic way and with concise arrow syntax.
Read tutorialThrottle a Function
Limit how often a function can run — great for scroll and resize handlers.
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