A trademark is any word, symbol, sign, device, or combination of them used to distinguish particular goods or services. Trademarks are technically limited to identification of goods. Such identification when applied to services is known as a service mark, but the two are often used interchangeably. In this text references to "trademark" or simply "mark" apply to both trademarks and service marks. A trade name or commercial name is any name used to identify a particular business. Although a trade name may acquire most of the same rights as a trademark, a trade name is not a trademark. A mark ordinarily identifies a particular product while a trade name identifies the business. Other symbols often considered similar to trademarks are certification marks and collective marks. The distinctions between the above should become more clear after examination of the following example.

Suppose Tom and Bud Jones invent a superior, pollution free wood stove in Tom's basement. They form a partnership and begin to build and sell the stoves under the name Jones Brothers Wood Stoves. Tom and Bud decide to sell the stoves under the name Benevolent Burners and affix a label with that mark to every stove. After the first year customers begin begging Tom and Bud to clean their chimneys using Tom and Bud's efficient cleaning method. The Jones brothers start cleaning chimneys and promoting their service as Cheery Chimney Sweeps. Jones Brothers Wood Stoves is the company's trade name, Benevolent Burners is a trademark, and Cheery Chimney Sweeps is a service mark. If some organization inspected wood burning stoves and approved the Benevolent Burner, would be authorized to place the organization's seal of approval or certification mark on the stoves. If the Jones brothers joined a national organization of chimney sweeps, they would be authorized to display the organization's collective mark.