Check out example codes for "w3 schools". It will help you in understanding the concepts better.
Code Example 1
<button onclick="myFunction()">Click Me!</button>
<script>
function myFunction() {
var x = document.getElementById("demo");
x.style.fontSize = "25px";
x.style.color = "red";
}
</script>
Code Example 2
MDN vs W3S: Civil War!
Code Example 3
Name: <input type="text" name="name">
E-mail: <input type="text" name="gdgdfgfdgfdg">
Website: <input type="text" name="website">
Comment: <textarea name="comment" rows="5" cols="40">
Code Example 4
Name: <input type="text" name="name">
E-mail: <input type="text" name="email">
Website: <input type="text" name="website">
Comment: <textarea name="comment" rows="5" cols="40">
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