flash (macromedia): I want to add a timer in my slide show so that every 10 secs or possibly
longer, my slide will change. or a tween will begin. I would like to know how
to do this in ActionScript, not any options that flash has to offer.

Hi

Read about setInterval in Flash Help, it will get ya started.

Im a little bit confused on what the setinterval() function does exactly. what
is the I saw a example where there was a this varible scope in the setinterval
like this setinterval(this, function, duration) what is the this doing
exactly. I know that it calls on a function and the duration was 20. but 20
what ?? 20 min, hours, days ???

to set a "timer" you need setInterval, which takes the function name and
interval in MILLISECONDS as parameters.

So, if you want function doThis() to be called every second, you write:

setInterval(doThis, 1000);

to be able to stop this repetition of the function you need to write this:

// to start the interval
my_interval = setInterval(doThis, 1000);

// to stop it
clearInterval(my_interval);