1) Computer access control 2) Software device 
The Linguists category is a listing of individuals working in or associated with the field of Linguistics. Most linguists are listed in subcategories of the Linguists by nationality category by their country of birth and/or the location of their linguistics work. Some linguists are also listed by field: see Historical linguists, Phonologists, Soci... Copy protection, also known as content protection, copy prevention and copy restriction, is any effort designed to prevent the reproduction of software, films, music, and other media, usually for copyright reasons. Various methods have been devised to prevent reproduction so that companies will gain benefit from each users who obtain a copy of the...
Method used by software manufacturers to prevent unauthorised copying.
a routine that is included in a program by its publisher to prevent the software from being duplicated except for a single backup copy.