Dominoes are simple enough to describe. They are two-sided tiles with numbers -- represented by dots -- on each side. Although they appear deceptively simple, domino tiles can form the basis for some incredibly complex games. It's difficult to nail down the exact moment that dominoes were invented, but historical researchers agree that they were invented in China. Most believe that they first arose in the early 1100s.

The Inventor

Chinese laborers who came to the United States claimed that the tiles were invented by Hung Ming, a romantic hero who came up with the tiles and games to entertain his soldiers. Other Chinese leaders who are said to have invented dominoes include Keung T'ai Kung and Fan Lai. Some printed sources and historical documents, however, say that the tiles were invented by a statesman and presented in 1120 to Emperor Hwui Tsung, but were not widely used until several years later. Eventually, sometime in the early 18th century, the tiles were introduced to the citizens of Europe.

The Sets

Dominoes arose from games played with two dice. The number of possible combinations of numbers when throwing two dice is 21, so traditional Chinese dominoes had at least 21 pieces. Some tiles were sometimes duplicated, however, giving each set varying numbers of tiles. Modern sets usually have 28 pieces, which includes one tile that has no dots and six tiles that have zero dots on one side only. Some sets are elaborately designed, with embossing and art.

The Tiles

Today's domino tiles are not the kind first used in China. "Western dominoes" have been around for only the past 250 years of so, according to the University of Waterloo. The dominoes used in China, however, don't actually look much different -- they are also flat and two-sided. But the small indentations -- called "pips" -- are different colors on each side. The tiles are also smaller than Western sets. The first dominoes were probably made of bone, but today they can be made of everything from bone and ivory to silver, plastic and even cardboard. Many are made of composite materials.

The Name

It was the Venetians who first called the tiles "dominoes." The name was adopted from a type of mask, called a "domini," that many people wore during the Venetian Carnival. The masks were white with black dots and were named for their resemblance to the black and white hoods that the Dominus, or Dominican monks, wore.

The Game

As with dice, the number of games that can be played with dominoes is limited only by the imagination. Most domino games require matching numbers to numbers, trying to win sets or getting rid of your tiles. The two games most commonly played in America are "Mexican Train" and "42," while "Muggins" and "Maltese Cross" are played in Britain.