There are two types of jQuery's each, the one iterates over and returns jQuery objects, the other is a more generic version.
Core/each
Example: Create a csv of all the hrefs on the page. (iterates over matching DOM elements and 'this' reffers to the current element)
var hrefs = "";
$("a").each(function() {
var href = $(this).attr('href');
if (href != undefined && href != "") {
hrefs = hrefs + (hrefs.length > 0 ? "," + href : href);
}
});
alert(hrefs);
Utilities/jQuery.each
Iterating over an array or the elements of an object:
$.each( { name: "John", lang: "JS" }, function(i, n){
alert( "Name: " + i + ", Value: " + n );
});
$.each( [0,1,2], function(i, n){
alert( "Item #" + i + ": " + n );
});