.attr()

Get the value of an attribute for the first element in the set of matched elements or set one or more attributes for every matched element.

event.data

An optional object of data passed to an event method when the current executing handler is bound.

Set default values for future Ajax requests. Its use is not recommended.

Also in: Effects > Custom

Creates an object containing a set of properties ready to be used in the definition of custom animations.

Attach a handler to an event for the elements. The handler is executed at most once per element per event type.