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JavaScript

The language every frontend and Node job assumes you already know — values, functions, this, and the async model that trips almost everyone up once.

Start the coursePractise this with real questions

In this course

  1. 1Values, types, and the equality traptypeof, truthy and falsy, and the one comparison operator to stop reaching for.7 min
  2. 2Scope, hoisting, and closuresvar against let and const, what hoisting actually moves, and the loop variable trap.8 min
  3. 3Arrays, objects, and the methods people actually usemap, filter and reduce over a hand-written loop, and the two ways to copy an object.8 min
  4. 4this, and the four ways it gets setCall-site rules, arrow functions, and the callback that loses its this.7 min
  5. 5From callbacks to async/awaitWhat a promise actually is, why await only pauses the function it is in, and the try/catch that never catches.8 min
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