Moving image from left to right and back again, etc...

[s_gibson86]

Hey, As the title describes, i am having a bit of trouble creating a script which will move an image back and forth across the screen. I have been to my lecturer for a bit of advice and hoping that he would point me in the right direction but no such luck. So far i have written the script to make it move from left to right across the screen but now i'm struggling to make it move right to left and so forth. I am new to Javascript so a nudge in the right direction would be a huge help. This is my script so far:Thank youSarah

var max_x = 1024var cup = document.getElementById("cup")var cup_x = 0function moveWin(){	cup_x = cup_x + 10	cup.style.left = cup_x + 'px'	if (cup_x <= max_x) {		timerID = setTimeout("moveWin()", 25)	}}function clicked(thing){	moveWin()}