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file
formats
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at
the level indicated by file extensions, e.g., .mp3
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as
indicated by Internet MediaType (aka MIME type), e.g. text/html
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versions
develop through time
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refinements
are tailored to specific purposes, e.g., TIFF-EP for electronic
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photography
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class
of related formats whose familial characteristics are important
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e.g.,
the WAVE audio format is an instance of the RIFF format class
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"wrappers"
distinguished in terms of their underlying bitstreams
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e.g.,
WAVE files may contain linear pulse code modulated [LPCM] audio
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(like
a CD) or highly compressed audio as used for digital telephony.
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file
formats may have optional features significant to sustainability
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e.g.
for encryption
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bundling
formats bind together files comprising a single digital work
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e.g.,
text and supporting illustrations, or a movie with sound tracks in
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different
languages
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