A trademark is a word, name, symbol or other device that a company uses to identify its products to the public. It's similar to a service mark, which identifies a company that deals in services rather than goods. There are some general rules concerning a trademark. In order to be distinctive, it can't be identified too closely with the product. A fruit company couldn't trademark the word 'banana,' because that's what they sell. Instead, they could copyright a stylized logo of a banana which is original artwork. On the other hand, an automobile manufacturer could trademark 'banana' as the name of a car model, since the word isn't ordinarily associated with the product. Some geographic names are also forbidden. You can't trademark Paris perfume or Texas Chili. Idaho potatoes and Philly cheesesteaks are generic names, not trademarks. You see trademarks every day on the products you use. Company logos are trademarks. So are advertising slogans. A trademark can even be a number, like 501 (five-oh-one) jeans or Heinz 57 Sauce. A trademark represents one or more products to the public. As such, it can be a valuable asset to a company, and is protected by law.