Let me know if you have questions about why this works and yours didn't.Code:var bgImage = new Array(); // don't change this bgImage[0] = "images/aboutus_1.jpg"; bgImage[1] = "images/1.jpg"; bgImage[2] = "images/2.jpg"; bgImage[3] = ""; function changeBG(bgImageIndex) { document.body.background = bgImage[bgImageIndex]; }