How to use clearInterval?

Answer 1

When you create your setinterval, make sure that you assign it to a variable so you can stop it later, especially if you have more than one running.

Example:

var helloInterval = setInterval(function(){ alert("Hello"); }, 3000);

To stop:
clearInterval(helloInterval);

Hope that helps.

Answer 2

clearInterval() will basically stop the setInterval() function you give it from running.
More info here: https://www.w3schools.com/jsref/met_win_clearinterval.asp