Intellectual property is knowledge or technology that is unique in some fashion such that the know-how it is based upon can be protected by law. Intellectual property includes patents, trademarks and copyright. Patents are usually based on a design, a process or a system of production. Trademarks are unique visual elements, such as a logo or product name, that help differentiate a business, product or service. Copyright generally relates to written materials such as a book or an article. In the U.S. all property rights that are intellectual-based may be protected by law through filing applications with the U.S. Patent and Trademark Office. Many lawyers are skilled in the application process for protecting these intellectual rights. While the subject property rights themselves can have an almost unlimited potential scope, to be protected under the law they must be unique in some way. Intellectual property lawyers help clients explain this uniqueness in their patent, trademark or copyright applications. Once approved, intellectual property is protected against infringement for a number of years and the owner of a patent, trademark or copyright can sue for damages and request injunctive relief.