Maybe A good blog

I have been working on AI:

var time:Number = 16.66;
var delay:Number = 16.66;

function walk(){
_root.circle._x += 3;
clearInterval(delay);
}

delay = setInterval(walk, time);

Sets two variables, creates a walk function, and the final line executes the walk function over an interval (setInterval). Delay is how often it executes the interval and time is how often it executes the function (I think).