• the new global functions setInterval() and clearInterval() provide javascript-like tools for timed execution of code.
• setInterval() runs a function or method every n milliseconds.

// Create a function to run after a countdown.
function helloWorld () {
  trace("Hi!");
}
// Call helloWorld() every 50 milliseconds.
setInterval(helloWorld, 50);

• Same thing, but with a function literal:

// Call function literal every 50 milliseconds.
setInterval(function () { trace("Hi!"); }, 50);

• Method version of setInterval():

// A method on the ball movie clip.
ball.move = function (xAmount, yAmount) {
  this._x += xAmount;
  this._y += yAmount;
  // Refresh the screen if the interval runs
  // faster than the framerate.
  updateAfterEvent();
}

// Call ball.move() every 50 milliseconds, passing
// the arguments 1 (xAmount) and -2 (yAmount).
// Arguments are only evaluated once.
setInterval(ball, "move", 50, 1, -2);

• A countdown that stops an interval from repeating endlessly:

// Create a function to run after a countdown.
function timesUp () {
  trace("Time's up!");
  // Stop the timer.
  clearInterval(timerInterval);
}
// Call timesUp() after 5000 milliseconds.
// Store the interval ID in a variable so we can stop the interval.
timerInterval = setInterval(timesUp, 5000);