what is event in reactjs code example

Example 1: react onclick to make another button

import React from 'react';

const App = () => {
  
const message = () => {
 console.log("Hello World!") 
}

return (
<button onClick={message}> Press me to print a message! </button>
  );
}

Example 2: react button onclick

import React from 'react';

function App() {

  function sayHello() {
    alert('Hello!');
  }
  
  return (
    <button onClick={sayHello}>
      Click me!
    </button>
  );
}

export default App;

Example 3: handling event in jsx

//Event hadling in react
function ActionLink() {
  function handleClick(e) {
    e.preventDefault();
    console.log('The link was clicked.');
  }

  return (
    <a href="#" onClick={handleClick}>
      Click me
    </a>
  );
}

Example 4: react button onclick

<button onClick={sayHello}>Click</button>