A bit of history, summarising from Bill Palmer's excellent webpage (see address at end):
Cups and Balls is the oldest trick known. Some incorrectly think it originated in ancient Egypt, though the oldest reference to them in any language is in the writings of Alciphron of Athens (300 AD).
15th century drawings show the trick was very popular in Europe, but the earliest textual reference in English is found in "Hocus Pocus Junior" (1634). Here, ten pages are devoted to the trick and its routine.
Today there are several different kinds of cups: standard, jumbo, miniature and Chop Cups (named after Al "Chop Chop" Wheatley who invented them around 1954). Each feature of the cup has a specific name (the mouth, the dimple or recess, the shoulder bead, etc), and it is traditional to perform the trick with a wand.
See
http://www.cupsandballsmuseum.com/ for images and more details.