The extension allows you to save audiovisual and textual information as a presentation or a slide show. Is used solely for viewing the created presentation and has no editing capabilities. It’s based on the XML format and can be opened with PowerPoint 2007 and newer versions. The file may be viewed by the users who do not own a commercial PC version of MS PowerPoint but who could still view the presentation using PowerPoint Viewer.
PGM is a storage format for grayscale images. Files in this format can be opened using software: ACDSee Photo Manager 14, ACD Systems Canvas 15, Corel PaintShop Pro X4. This type of file can be edited with a text editor. PGM files can be in two versions: P2 / P5. P2 are readable, P5 - to binary formats.