jQuery()

Return a collection of matched elements either found in the DOM based on passed argument(s) or created by passing an HTML string.

jQuery.Deferred()

A factory function that returns a chainable utility object with methods to register multiple callbacks into callback queues, invoke callback queues, and relay the success or failure state of any synchronous or asynchronous function.

.map()

Pass each element in the current matched set through a function, producing a new jQuery object containing the return values.