How does the render() method work in React?

Question

Node.js

As far as I know, passing a parameter of this type is not supported in JS. return returns parenthesized html code and not in quotes, and not in ` ` as a string.
Before building, the React compiler parses the data in the component files (namely, those that the render function returns) and translates them into a working form for ES6, or is it normal for ES6. (I understand that react builds everything in ES2015 )

render() {
    return (
      <Row className="show-grid">
        <Col md={6}>
          <h2>Est. total</h2>
        </Col>
        <Col md={6}>
          <h2>{`$${this.props.price}`}</h2>
        </Col>
      </Row>
    );
  }

Answer 1

return returns parenthesized html code

return does not return html code. JSX is just syntactic sugar on top of JavaScript .
jsx like:

render() {
  return (
    <h1 className="greeting">
      Hello, world!
    </h1>
  );
}

is translated into JS of the form:

render() {
  return React.createElement(
    'h1',
    { className: 'greeting' },
    'Hello, world!'
  );
}

the result of executing render in this case will be the following:

{
  $$typeof: Symbol(react.element),
  key: null,
  props: { className: "greeting", children: "Hello, world!" },
  ref: null,
  type: "h1",
  _owner: null,
  _store: { validated: false },
  _self: null,
  _source: null,
  __proto__: Object,
}

The returned object is a Virtual DOM Node . According to it, the library creates an element in the real DOM .
React compiler parses data in component files before building...
...I understand that React builds everything in ES2015...
No. JSX is not part of the ECMAScript 2015 specification