The family of psittacines, or parrot family, is that which contains the Amazon and African Gray parrots and their various sub-species and relatives, cockatoos, macaws, budgies and many more.
They are almost all noted for their ability to mimic human speech, amongst other sounds, and the larger birds can develop large vocabularies well into the hundreds of words. There has also been research to suggest that African Gray parrots can attribute concepts to words and can even string their own phrases and sentences together to signify a concept they hadn't yet been taught a word for.
(See: "STUDIES TO DETERMINE THE INTELLIGENCE OF AFRICAN GREY PARROTS", by Irene M. Pepperberg, Ph.D)
Joanna Burger also mentions her Red Lored Amazon parrot's propensity for tool use in her book "The Parrot Who Owns Me" (Publisher: Random House, Incorporated) in which it seems to learn how to scratch its neck-feathers with a discarded quill, not by trial and error (heuristic learning) but rather by conceptual thought, the process of working out a problem and its solution mentally before acting upon it.
The larger birds can also be very long lived in captivity, macaws lasting from 30 - 50 years, cockatoos from 20 - 30 years and Amazons from 50 - 80 years, some even reaching beyond their 100th birthday. This means that if one is thinking of acquiring one as a pet it may be wise to consider who will inherit it.