CBS Inc. (CBS) is a major American television network. CBS started out as a radio network. The name is derived from the initials of the network's former name, Columbia Broadcasting System. The network is sometimes referred to as the Eye Network or more simply The Eye, in reference to the shape of the company's logo. It has also been called the Tiffany Network, which alludes to the perceived high quality of CBS programming during the tenure of its founder William S. Paley (1901–90). It can also refer to some of CBS's first demonstrations of color television, which were held in a former Tiffany & Co. building in New York City in 1950, thus earning it the name "Color broadcasting system" back when such a feat was innovative.

The network has its origins in United Independent Broadcasters Inc., a collection of 16 radio stations that was bought by William S. Paley in 1928 and renamed the Columbia Broadcasting System. Under Paley's guidance, CBS would first become one of the largest radio networks in the United States and then one of the big three American broadcast television networks. In 1974, CBS dropped its full name and became known simply as CBS, Inc. The Westinghouse Electric Corporation acquired the network in 1995 and eventually adopted the name of the company it had bought to become CBS Corporation. In 2000, CBS came under the control of Viacom, which coincidentally had begun as a spin-off of CBS in 1971. In late 2005, Viacom split itself and reestablished CBS Corporation with the CBS television network at its core. CBS Corporation and the new Viacom are controlled by Sumner Redstone through National Amusements, the parent of the two companies.