By creating an Audio object you can play sounds. In this example a sound will play when I press the Left Arrow key. If you don't hear anything try to find a different link. Only .wav files have been tested. Another note; when creating the Audio object, wrap it inside a function like in this example.
var subtitle = ""; var playSound = function(){ var url = "http://www.wavsource.com/snds_2018-01-14_3453803176249356/sfx/applause_y.wav"; var applause = new Audio(url); if(keyCode === LEFT){ applause.play(); subtitle = "Applause"; } }; var keyPressed = function() { background(255); playSound(); fill(0); textSize(50); textAlign(CENTER,CENTER); text(subtitle,200,200); };