Abax
An abax was a table covered with sand commonly used by students, particularly in Greece, to perform studies such as writing, geometry, and calculations.
An abax was the predecessor to the abacus. Objects, such as stones, were added for counting and then columns for place valued arithmetic. The demarcation between an abax and an abacus seems to be poorly defined in history, moreover, modern definitions of the word "abacus" universally describe it as a frame with rods and beads and, in general, do not include the definition of "sand table".
The sand table may well have been the predecessor to some board games. ("The word abax, or abacus, is used both for the reckoning-board with its counters and the play-board with its pieces, ...") Abax is from the old Greek for "Sand Table".
Read more about this topic: Sand Table