File Extension

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A File Extension is a suffix associated with a Filename that conventionally identifies a file format, file type, or intended interpretation.

Examples include:

pdf
json
xml
svg
md

For example, in:

test-results.json

the File Extension is:

json

A File Extension is conventionally associated with the interpretation of a file, but it does not establish that the contents of the file actually conform to the indicated format.

For example, a file named:

report.pdf

may have the File Extension pdf, but the extension alone does not establish that the contents constitute a valid PDF document.

Some Filenames do not contain a File Extension.

Examples include:

README
LICENSE
Makefile

The syntax used to separate a File Extension from the remainder of a Filename is determined by the applicable naming convention or environment.

A suffix associated with a Filename that conventionally identifies a file format, file type, or intended interpretation.

• DIDO Solutions

A File Extension is optional unless required by an applicable policy, naming convention, or environment.

A File Extension provides an indication of intended file interpretation and does not, by itself, establish conformance of the file contents to a particular file format.

The separator used between the Filename stem and the File Extension is representation-dependent.

For the Filename:

architecture.svg

the File Extension is:

svg

For the Filename:

README

no File Extension is present.