An Element is a plain object describing what you want to appear on the screen in terms of the DOM nodes or other components. Elements can contain other Elements in their props. Creating a React element is cheap. Once an element is created, it is never mutated.
The object representation of React Element would be as follows:
const element = React.createElement(
'div',
{id: 'login-btn'},
'Login'
)
The above React.createElement() function returns an object:
{
type: 'div',
props: {
children: 'Login',
id: 'login-btn'
}
}
And finally it renders to the DOM using ReactDOM.render():
<div id='login-btn'>Login</div>
Whereas a component can be declared in several different ways. It can be a class with a render() method. Alternatively, in simple cases, it can be defined as a function. In either case, it takes props as an input, and returns a JSX tree as the output:
const Button = ({ onLogin }) =>
<div id={'login-btn'} onClick={onLogin}>Login</div>
Then JSX gets transpiled to a React.createElement() function tree:
const Button = ({ onLogin }) => React.createElement(
'div',
{ id: 'login-btn', onClick: onLogin },
'Login'
)
