A PowerPoint Template is a file that can contain commonly used settings to make producing future PowerPoint Presentations and Shows easier. POTX PowerPoint Templates are different than the POT version in that they use the Microsoft Office Open XML format.
DOTM file has two attributes namely Zip file compression and XML (Extensive Markup Language). It is identical to .DOCX and .DOCM file in which the M stands for macro and the X stands for XML. The application that can open both .DOCX and .DOCM is via Microsoft Word version 2007 or 2010.