The onmousedown event triggers when a mouse button is pressed.
Example
You can try to run the following code to learn how to work with onmousedown event in JavaScript −
<html>
<head>
<script>
<!--
function sayHello() {
alert("You clicked here.")
}
//-->
</script>
</head>
<body>
<p onmousedown = "sayHello()">This is demo text. The onmousedown event triggers when a mouse button is pressed</p>
</body>
</html>