Censor bars

Censor bars (often known as black bars or censor boxes) are a basic form of text, photography, and videocensorship in which "sensitive" information or images are occluded by black, gray, or even white rectangular boxes. These bars have been used to censor various parts of images. Since the creation of digital editing software which can apply less obtrusive effects such as pixelization and blurring, censor bars are usually only used for satire.

A 1965 FBI surveillance photograph

A heavily redacted page from the lawsuit American Civil Liberties Union v. Ashcroft

The censor bar as used by Google in the SOPA and PIPA online protests

Censor bars applied to an academy painting

Censor bars applied to a photo

Identity masking of a human face

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