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 person who obtains an authorized copy of their product. Unauthorized copying and distribution accounted for $2.4 billion in lost revenue in the United States alone in the 1990s, and is assumed to be causing impact on revenues in the music and the game industry, leading to proposal of stricter copyright laws such as PIPA. Some methods of copy protection have also led to criticisms because it caused inconvenience for honest consumers, or it secretly installed additional or unwan