template extension

The term document template used in the context of file format refers to a common feature of many software applications that define a unique non-executable file format intended specifically for that particular application.
Template file formats are those whose file extension indicates that the file type is intended as a high starting point from which to create other files.

These types of files are usually indicated on the Save As ... file dialog box of the application.
For example, the word processing application Microsoft Word uses different file extensions for documents and templates: In Word 2003 the file extension .dot is used to indicate a template, in contrast to .doc for a standard document. In Word 2007, it's .dotx, instead of .docx for documents.
The OpenDocument Format also has templates in its specification, with .ott as the filename extension for OpenDocument Text template.
In Adobe Dreamweaver the .dwt extension is used to indicate a template.

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