Trademark is a word or words, a name, a design, a picture, a sound, or any other symbol that distinguishes the products of one company from those of another. A trademark also may consist of any combination of these identifications. Most trademarks appear on the product, on its container, or in advertisements for the product. A service mark identifies the source of a service rather than a product. For example, an electric company may use a light bulb as a symbol of the service it offers to its customers.