Definitions[edit | edit source]

Data[edit | edit source]

A filter is

[a] pattern or mask through which data is passed to separate specified items. For instance, a filter used in e-mail or in retrieving newsgroup messages can allow users to automatically discard messages from designated users.[1]

Telecommunications[edit | edit source]

A filter is

[a]n arrangement of electronic components designed to pass signals in one or several frequency bands and to attenuate signals in other frequency bands.[2]

Overview[edit | edit source]

Filters, designed originally to screen out pornography, can also be used to provide automatic inclusion or exclusion of elements and pieces from various information sources. They might be used to combine two or more Web pages together, for example, or rearrange their elements. They might also be used to delete advertising from a Web page.

Filtering technology both overblocks and underblocks content. Filters are not generally restricted to one type of Internet application or one type of content, such as video or audio programming. Instead, generally, filters are designed to work on any application or content with which a user might interact, including websites, e-mail, instant messaging, chat rooms, and other activities.

According to the U.S. Supreme Court:

Filters . . . impose selective restrictions on speech at the receiving end, not universal restrictions at the source. Under a filtering regime, adults without children may gain access to speech they have a right to see without having to identify themselves or provide their credit card information. Even adults with children may obtain access to the same speech on the same terms simply by turning off the filter on their home computers. Above all, promoting the use of filters does not condemn as criminal any category of speech, and so the potential chilling effect is eliminated, or at least much diminished.[3]

Types of filters[edit | edit source]

Filters generally follow one of three strategies:

Copyright issues[edit | edit source]

When an Internet user makes use of filtering software to alter a copyrightable work such as a Web page, does that user infringe the right of the copyright owner to authorize the preparation of derivative works?

References[edit | edit source]

See also[edit | edit source]

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