Many sources, including official tutorials and guides, often describe JSX as "JavaScript XML", but the official React documentation doesn't explicitly define JSX that way.

What JSX Actually Is:

JSX is a syntax extension for JavaScript that looks similar to XML or HTML but is ultimately compiled into JavaScript. React's official documentation describes it as:

JSX is a syntax extension for JavaScript. It is used with React to describe what the UI should look like. React Docs

While JSX resembles XML/HTML, it's not exactly the same, and React itself doesn't formally call it "JavaScript XML." Instead, JSX gets transpiled into JavaScript function calls using Babel.

For example:

jsx

const element = Hello, JSX!;

Compiles to: Js code

const element = React.createElement("h1", null, "Hello, JSX!");

Why Is It Called "JavaScript XML"?

1. The term JavaScript XML (JSX) likely became popular because JSX looks like XML and is used to structure UI elements.

2. However, JSX is not XML—it just borrows some of its syntax.