This in turn requires the use of technical censorship methods that are unique to the Internet, such as site blocking and content filtering.
The great diversity of available sources for use in modern history classes requires that selections be made with great care - since virtually unlimited material is available.
The goals here are: Efforts have been made to confirm to US Copyright Law.
According to Global Web Index, over 400 million people use virtual private networks to circumvent censorship or for increased level of privacy.
Many of the changes associated with Internet censorship are similar to those for offline censorship of more traditional media such as newspapers, magazines, books, music, radio, television, and film.
Countries may filter sensitive content on an ongoing basis and/or introduce temporary filtering during key time periods such as elections.