//single event i.e. alarm, time in milliseconds
var timeout = setTimeout(function(){yourFunction()},10000);
//repeated events, gap in milliseconds
var interval = setInterval(function(){yourFunction()},1000);document.getElementById("gameStart").addEventListener("click", function(){
var timeleft = 15;
var downloadTimer = setInterval(function function1(){
document.getElementById("countdown").innerHTML = timeleft +
" "+"seconds remaining";
timeleft -= 1;
if(timeleft <= 0){
clearInterval(downloadTimer);
document.getElementById("countdown").innerHTML = "Time is up!"
}
}, 1000);
console.log(countdown);
});