Generally speaking, protection for intellectual property extends to intellectual creations in order to incentivize innovation, and depends upon the nature of the work and its "characteristics". The main types of intellectual property law are: copyright, which protects creative works; patent, which protects invention; trade secret, which protects information not generally known or readily ascertainable that is valuable to the secret holder; and trademark, which protects branding and other exclusive properties of products and services. Any matter that meets these criteria can be protected. However, "sui generis" statutes exist in many countries that extend intellectual property protection to matter that does not meet characteristic definitions: integrated circuit layouts, ship hull designs, fashion designs in France, databases, or plant varieties require "sui generis" statutes because of their unique characteristics. The United States, Japan, Australia and many EU countries protect the topography of semiconductor chips and integrated circuits under "sui generis" laws, which borrow some aspects from patent or copyright law. In the U.S. this "sui generis" law is known as the Semiconductor Chip Protection Act of 1984. In statutory interpretation, it refers to the problem of giving meaning to groups of words where one of the words is ambiguous or inherently unclear. For example, in road traffic law, a statute may require consideration of large vehicles separately from other vehicles. The word "large" is ambiguous per se, but may be considered "heavy". Thus the relevant legislation (in Australian law) contains a section called "Terms used" or "Definitions" that itemises all words considered ambiguous, and confers specific interpretations consistent with natural language. So, this list tells us that "heavy vehicle" means a vehicle with a "GVM" over 4.5 tons, and "GVM" means "gross vehicle mass", the maximum loaded mass of the vehicle. Further explanations cover various contingencies. Thus, "large" is equivalent to "heavy" and is (for this unique case) clearly defined "sui generis". In United Kingdom town planning law, in particular relating to the Town and Country Planning (Use Classes) Order 1987, many common types of land use are categorised into specific "use classes". Change of use of land "within" a use class does not require planning permission; however, changing "between" use classes might require planning permission, and permission is always required if the new use is "sui generis". Examples of "sui generis" uses include embassies, theatres, amusement arcades, laundrettes, taxi or vehicle hire businesses, petrol filling stations, scrapyards, nightclubs, motor car showrooms, retail warehouses, clubs and hostels.