====== File Extension ======

[[dido:99_annexes:annex-b-terms-and-definitions:start|Go up to Terms and Definitions]]

===== Discussion =====

A **File Extension** is a suffix associated with a [[dido:99_annexes:annex-b-terms-and-definitions:f:filename|Filename]] that conventionally identifies a file format, file type, or intended interpretation.

Examples include:

><code>
pdf
json
xml
svg
md
</code>

For example, in:

><code>
test-results.json
</code>

the File Extension is:

><code>
json
</code>

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:

><code>
report.pdf
</code>

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:

><code>
README
LICENSE
Makefile
</code>

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

===== Definition =====

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

===== Source =====

  * DIDO Solutions

===== Note =====

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.

===== Example =====

For the Filename:

><code>
architecture.svg
</code>

the File Extension is:

><code>
svg
</code>

For the Filename:

><code>
README
</code>

no File Extension is present.

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