function preload(){
    var imgNames = new Array(
        "/img/iconDocOver.jpg",
        "/img/iconExeOver.jpg",
        "/img/iconFileOver.jpg",
        "/img/iconFolderOver.jpg",
        "/img/iconZipOver.jpg"      
    );
    var images = new Array();
    for( var i=0; i<imgNames.length; i++ ){
        images[i] = new Image();
        images[i].src = imgNames[i];
    }
}