JSX is a new language that compiles down to JavaScript. It allows developers to define components of the UI in an HTML-like syntax. Instead of using document.createElement(), React.createElement(), or a templating engine, you can write your component in JSX. JSX is like a template, in the sense that you can add placeholders within the template that'll be substituted with real data. The difference is that JSX gets compiled down to plain JavaScript, which means you can use any JavaScript syntax directly inside a JSX file.
If you're familiar with CSS preprocessors, you can think of JSX as the preprocessor for HTML, similar to what Sass does for CSS. The introduction of JSX means developers have a much easier way to visualize their UI components ...
