What is JSX?

A JSX element compiles into what is known as a reactElement. JSX converts html style syntax into a reactElement class for us.

For example: <h1 className="emphasis" /> compiles to: var element = React.createElement('h1', { className: 'emphasis '});

Rendering

ReactDOM.render(
  <h1 className="emphasis" />,
  document.getElementById('react-element')
);

Would be compiled to:

ReactDOM.render(
   element,
   document.getElementById('react-element')
);

Converting HTML to JSX

Facebook has provided a tool that converts HTML to JSX.