A marble is a small spherical toy often made from glass, clay, steel, plastic, or agate. These balls vary in size. Most commonly, they are about 13 mm in diameter, but they may range from less than 1 mm to over 8 cm , while some art glass marbles for display purposes are over 30 cm wide. Marbles can be used for a variety of games called marbles. They are often collected, both for nostalgia and for their aesthetic colors. In the North of England the objects and the game are called "taws", with larger taws being called bottle washers after the use of a marble in Codd-neck bottles, which were often collected for play. These toys can be used to make marble runs, a form of art, or they can be used in marble races, a type of race using marbles.
In the early twentieth century, small balls of stone from about 2500 BCE, identified by archaeologists as marbles, were found by excavation near Mohenjo-daro. Marbles are often mentioned in Roman literature, as in Ovid's poem Nux (which mentions playing the game with walnuts), and there are many examples of marbles from excavations of sites associated with Chaldeans of Mesopotamia and ancient Egypt. They were commonly made of clay, stone or glass. Marbles arrived in Britain, imported from the Low Countries, during the medieval era.