A trademark identifies the brand owner of a particular product or service. It could be a sign, design, or expression which identifies products or services of a particular source. It may be located on a package, a label, or on the product itself. The essential function of a trademark is to exclusively identify the commercial source or origin of products or services. The trademark owner can be an individual, business organization, or any legal entity. For the sake of corporate identity, trademarks are often displayed on company buildings.