JSX Short Examples:
const h1 = <h1>Hello world</h1>;
const navBar = <nav>I am a nav bar</nav>;

JSX stored as an Object:
const navbar = {
  home: <li>Home</li>,
  about: <li>About</li>,
  contact: <li>Contact</li>,
  signUp: <li>Sign Up</li>
};

JSX is a language made to be used with React. Written in JS files and treated as JavaScript expressions. Add JavaScript code to JSX elements using curly braces { }.

const example = (
  <>
  <h1> Header Title <h1>
  <p> Paragraph </p>
  </> 
);

JSX expressions must have an outermost element. Either <div> </div> or fragments <> </> could be used in order for it to render.

<div className="classes"></div>

To add classes use className.

Some examples:
const element = <a href="www.com"> link </a>; 
const img1 = <img src={imgSavedToAVar}></img>;

Example using camelCase:
<button className="styleButton" onClick={func}> Click </button> 

React uses camelCase naming convention to use HTML Attributes. Ex: tabindex = tabIndex, onclick = onClick

Old method:
import React from 'react';
import ReactDOM from 'react-dom';

ReactDOM.render(<h1>Hello world</h1>, document.getElementById('app')); 

New method:
import React from 'react';
import { createRoot } from 'react-dom/client';

const container = document.getElementById('app');
const root = createRoot(container);
root.render(<App />);

To render JSX inside a HTML DOM element.

<br />  // Represents a line break
<hr />  // Represents a horizontal rule or divider
<img src="" alt="" /> // Represents an image
<input type="" /> // Represents an input element

All tags must be properly closed, but some tags are self-closing tags.

const example = (
  <a href="https://link.com">
    <h1>
      Click here
    </h1>
  </a>
);

Use parentheses if you have nested multiline JSX.

const name = 'First Name';
const element = <h1>Hello, {name}</h1>;

Clock example:
function Clock() {
  const date = new Date()
  const hours = date.getHours() % 12
    
  return (
    <h1>It is currently about {hours} o'clock!</h1>
  )
}

Image example:
<img src={`../images/${props.img}`} />

To use JavaScript in JSX use curly braces.