JavaScript
Introduction to JavaScript Frameworks
What a framework actually does for you, how React, Vue, Svelte and Angular differ, and how to tell whether you need one…
JavaScript
How JavaScript actually works in the browser. Variables, functions, the DOM, events and async code, explained with examples you can paste into a console.
32 guides
JavaScript
The JavaScript Double Exclamation Mark, Explained
What the double exclamation mark actually does in JavaScript, why it is not an operator, when it is genuinely useful, and when…
JavaScript
TypeScript vs JavaScript: Which Should a Beginner Learn?
TypeScript is JavaScript with types checked before the code runs. What that buys, what it costs, and a clear answer on learning…
JavaScript
Introduction to ES6 and Beyond
The JavaScript features added since 2015 that changed how the language is written: let and const, arrow functions, destructuring, modules, async/await and…
JavaScript
TypeScript 7: What the Native Compiler Changes for You
TypeScript 7 replaced the JavaScript-based compiler with a port written in Go. Builds and editor checks are several times faster. What changed,…
JavaScript
Fixing “error is of type unknown” in TypeScript catch Blocks
Since TypeScript 4.4, a caught value is unknown, not any. Why that is correct, the three ways to handle it, and a…
JavaScript
Fixing “TypeError: x is not a constructor”
You used new on something that cannot be constructed: an arrow function, an object, an undefined import, or a module instead of…
JavaScript
Working with Browser Storage in JavaScript
localStorage, sessionStorage, cookies and IndexedDB compared — what each is for, the quota and JSON traps, and what should never go in…
JavaScript
JavaScript Not Running From Your HTML File
The script tag is there and nothing happens, or the console is empty. Script placement, defer, wrong paths, cached files and browser…
JavaScript
JavaScript Basics
The syntax of JavaScript in one page: variables, types, operators, functions, conditions, loops, arrays, objects and the mistakes beginners make with each.
JavaScript
Introduction to JavaScript
What JavaScript is, where it runs, what it is used for, and how it relates to HTML and CSS — plus your…
JavaScript
Arrays and Objects in JavaScript
The two structures JavaScript is built on: how to create, read, update and loop over each, plus copying, destructuring and the reference…
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Where to go next
Programming Basics
The ideas every language shares — variables, loops, functions and how a program actually runs.
17 guides
Python
Plain-English Python guides, from your first line of code to small programs that do real work.
72 guides
Web Development
HTML, CSS and the pieces that turn code into a page people can visit.
13 guides
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