Web filter

Content-control software is software designed to restrict or control the content a reader is authorised to access, especially when utilised to restrict material delivered over the Internet via the Web, e-mail, or other means. Content-control software determines what content will be available or be blocked.

Such restrictions can be applied at various levels: a government can attempt to apply them nationwide (see Internet censorship), or they can, for example, be applied by an ISP to its clients, by an employer to its personnel, by a school to its students, by a library to its visitors, by a parent to a child's computer, or by an individual user to his or her own computer.

The motive is often to prevent access to content which the computer's owner(s) or other authorities may consider objectionable. When imposed without the consent of the user, content control can be characterised as a form of internet censorship. Some content-control software includes time control functions that empowers parents to set the amount of time that child may spend accessing the Internet or playing games or other computer activities.

In some countries, such software is ubiquitous. In Cuba, if a computer user at a government-controlled Internet cafe types certain words, the word processor or browser is automatically closed, and a "state security" warning is given.

The term "content control" is used on occasion by CNN,Playboy magazine, the San Francisco Chronicle, and The New York Times. However, several other terms, including "content filtering software", "secure web gateways", "censorware", "content security and control", "web filtering software", "content-censoring software", and "content-blocking software", are often used. "Nannyware" has also been used in both product marketing and by the media. Industry research company Gartner uses "secure web gateway" (SWG) to describe the market segment.

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Wikipedia