A trademark (also written trade mark or trade-mark) is a type of intellectual property consisting of a recognizable sign, design, or expression that identifies products or services from a particular source and distinguishes them from others. The trademark owner can be an individual, business organization, or any legal entity. A trademark may be located on a package, a label, a voucher, or on the product itself. Trademarks used to identify services are sometimes called service marks.

In the past, The first legislative act concerning trademarks was passed in 1266 under the reign of Henry the 3rd of England requiring all bakers to use a distinctive mark for the bread they sold. The first modern trademark laws emerged in the late 19th century. In France, the first comprehensive trademark system in the world was passed into law in 1857. The Trade Marks Act 1938 of the United Kingdom changed the system, permitting registration based on "intent-to-use", creating an examination based process, and creating an application publication system. The 1938 Act, which served as a model for similar legislation elsewhere, contained other novel concepts such as "associated trademarks", a consent to use the system, a defensive mark system, and a non claiming right system.

The symbols symbol) and the registered trademark symbol can be used to indicate trademarks; the latter is only for use by the owner of a trademark that has been registered.

Usage.

A trademark identifies the brand owner of a particular product, media, company, Movie or TV series, characters or service. Trademarks can be used by others under licensing agreements; for example, Bullyland obtained a license to produce Smurf figurines; the Lego Group purchased a license from Lucasfilm to be allowed to launch Lego Star Wars; and TT Toys Toys is a manufacturer of licensed ride-on replica cars for children. The unauthorized usage of trademarks by producing and trading counterfeit consumer goods is known as brand piracy.

The owner of a trademark may pursue legal action against trademark infringement. Most countries require formal trademark registration as a precondition for pursuing this type of action. The United States, Canada, and other countries also recognize common law trademark rights, which means action can be taken to protect any unregistered trademark if it is in use. Still, common law trademarks offer to the holder, in general, less legal protection than registered trademarks.

As the purpose of the trademark is to identify a particular source of the product, rather than the product itself, it is widespread legal advice that trademark owners should always use their trademarks as adjectives modifying a generic product name, and set off with capitalization or a distinctive typeface, as a guard against the trademark becoming the generic name of the product. Thus "LEGO bricks" rather than "some Lego" or "Legos". The name of the producer itself is a "trade name" rather than a trademark and can be used as a noun.