for loop

gistfile1.js

var anchors = document.getElementsByTagName("a");
for (var i = 0, j = anchors.length; i < j; i += 1) {
	// do some stuff here
}

var anchors = document.getElementsByTagName("a");
for (var i = anchors.length; i > 0; i -= 1) {
	// do some stuff here
}

for (var i=0, item; item = someArray[i]; i++) {
alert(item);
}