Why return this.each(function()) in jQuery plugins?

Question

Some of the tutorials and examples I have seen for developing jQuery plugins tend to return

this.each(function () {
    //Plugin code here
});

Answer 1

Let me show you two "equivalent" pieces of code that could clarify your question:

With jQuery "each" function:

(function($) {
    $.fn.mangle = function(options) {
        return this.each(function() {
            $(this).append(' - ' + $(this).data('x'));
        });
    };
})(jQuery);

Without jQuery "each" function:

(function($) {
    $.fn.mangle = function(options) {
        var objs = this;
        for (var i=0; i

So, basically, each function is used to apply some code to all elements contained in this object (as this usually refers to a group of elements returned by a jQuery selector) and return the reference to this (as each function always returns that reference -to allow chaining calls-)

As a side note: The second approach (-for loop-) is faster (notably on old browsers) than former one (-each function-).