how to use setTimeout in js code example

Example 1: javascript settimeout

setTimeout(function(){
 	alert("Sup!"); 
}, 2000);//wait 2 seconds

Example 2: javascript settimeout

setTimeout(function(){ alert("Hello"); }, 3000);

Example 3: js after settimeout

function doHomeWork(subject, callback){
    setTimeout(callback,500);
    console.log("doing my homework:", subject)
}

doHomeWork("Maths", function(){console.log("finished my homework");});