A counter is something like:
var Counter = 0;
var Something = false;
if (Something == true) { // Set Something to equal true when you want the counter to activate
Counter += 1;
}
if (Counter == 10) {
// Do the function you want.
}
A timer interval uses real time instead of flash time so you can accurately measure seconds, minutes, hours etc.
You can use this as a timer:
function TimeFunction() {
// Do something
}
IntervalOfTimer = setInterval(TimeFunction, 1000); // 1000mili seconds = 1 second
All you would do is set the setInterval off when your event happends and then remove it within the TimeFunction so it will only run once.
Remove with:
clearInterval(IntervalOfTimer);