Check out example codes for "button functions html". It will help you in understanding the concepts better.
Code Example 1
<button onclick="myFunction()">Click me</button>
<p id="demo"></p>
<script>
function myFunction() {
document.getElementById("demo").innerHTML = "Hello World";
}
</script>
Code Example 2
<script>
function myFunction() {
alert("ALERT");
}
</script>
<button onclick="myFunction">Click</button>
Code Example 3
<script>
$(document).ready(function(){
$('#MyButton').click(function(){
CapacityChart();
});
});
</script>
<input type="button" value="Capacity Chart" id="MyButton" >
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