Learn javascript
Short lessons written around the screening tests employers use. Read one, then take the test.
Scope, hoisting and closures in JavaScriptHow var, let and const differ, what hoisting really does, and why closures inside loops behave as they do.Lesson 1
Promises, async/await and the event loopWhy asynchronous code logs in the order it does, and how to write and handle promises and async functions safely.Lesson 2
Equality, type coercion and what this points toPredict == versus ===, truthy and falsy values, the ?? operator, and why a method loses this when you pass it around.Lesson 3
Array methods, spread and destructuringChain map, filter and reduce correctly, sort numbers without surprises, and copy arrays and objects instead of sharing them.Lesson 4
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