function hover() {var images = new Array(
//setting id name
document.getElementById('button'),
document.getElementById('button2'),
document.getElementById('button3'),
document.getElementById('button4'),
document.getElementById('button5'),
document.getElementById('button6')



//setting end




);

for(var i=0; i < images.length; i++) {
images[i].onmouseover = function() {this.setAttribute("src", this.getAttribute("src").replace("_out.", "_over."));}
images[i].onmouseout = function() {this.setAttribute("src", this.getAttribute("src").replace("_over.", "_out."));}
}

}
//Start
hover()



//document.getElementById( id );