Microsoft uses Open XML based structure when any of its application is making office documents like Word, PowerPoint etc. The PPSX file format is used by Microsoft PowerPoint to store a file as a slideshow.
This file can be used just like any PowerPoint file but the main difference between this file and any other PowerPoint presentation file is that this file is not editable by the user and is only used for displaying the data. The user cannot change the contents or elements of the file and the contents are just shown as a series of slides when opened by the user.
