They are: Calling .waypoint with no parameters will register the elements as waypoints using the default options. The elements will fire the waypoint.reached e

They are: Calling .waypoint with no parameters will register the elements as waypoints using the default options. The elements will fire the waypoint.reached event, but calling it in this way does not bind any handler to the event. You can bind to the event yourself, as with any other event, like so: someElements.bind('waypoint.reached', function(event, direction) { // make it rain }); Calling .waypoint with a function is just a shortcut for that.