JavaScript Essentials for Freelance Web Developers
This guide explores JavaScript essentials for freelance web developers. It covers fundamental concepts, practical examples, and tips for mastering JavaScript.
Articles
React, page 3 of 3
React is a declarative and flexible JavaScript library used for building user interfaces and applications. Amongst many other things, it allows you to compose your application UIs from components and offers an accessible route into more complex programming on the front end.
Below you will find a subset of articles from my blog specifically about React. This is an area that I have worked with for many years, and have managed to write about quite a few times. There are forty collected together for you below.
JavaScript Essentials for Freelance Web Developers. 
Rendering Lists in React and Why Keys Matter. Rendering Lists in React and Why Keys Matter
Render lists in React with stable keys, avoiding index and random‑key bugs, preserving component state correctly through filtering, sorting, and reordering.
Controlled vs. Uncontrolled Components in React. Controlled vs. Uncontrolled Components in React
Controlled vs. uncontrolled components in React explained with form examples, refs, validation trade‑offs, and why each approach suits different jobs.
Lifting State up in React. Lifting State up in React
Lifting state up in React explained clearly, including shared state, single sources of truth, child callbacks, and when moving state higher helps.