Trademark distinctiveness is an important concept in the law governing trademarks and service marks. A trademark may be eligible for registration, or registrable, if amongst other things it performs the essential trademark function, and has distinctive character. Registrability can be understood as a continuum, with "inherently distinctive" marks at one end, "generic" and "descriptive" marks with no distinctive character at the other end, and "suggestive" and "arbitrary" marks lying between these two points. This part of registration is known as Section 3 of the trademark act in the UK as opposed to Section 5 which is concerned with prior rights of others. A mark must satisfy both sections to become registered.