Node item(unsigned long index);
index
The position of the element to be returned. Elements appear in an HTMLCollection in the same order in which they appear in the document source.
The element at the specified index, or null if index is less than zero or greater than or equal to the length property.
The item( ) method returns a numbered element from an HTMLCollection. In JavaScript, it is easier to treat the HTMLCollection as an array and to index it using array notation.
var c = document.images; // This is an HTMLCollection var img0 = c.item(0); // You can use the item( ) method this way var img1 = c[1]; // But this notation is easier and more common