As of jQuery 1.5, the Deferred object provides a way to register multiple callbacks into self-managed callback queues, invoke callback queues as appropriate, and relay the success or failure state of any synchronous or asynchronous function.
This object provides a subset of the methods of the Deferred object (then, done, fail, always, pipe. isResolved, and isRejected) to prevent users from changing the state of the Deferred.
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This object provides a subset of the methods of the Deferred object (then, done, fail, always, pipe, and state) to prevent users from changing the state of the Deferred.
A multi-purpose object that provides a powerful way to manage callback lists. It supports adding, removing, firing, and disabling callbacks. The Callbacks object is created and returned by the $.Callbacks function and subsequently returned by most of that function's methods.