DGN files are drawings created by and supported by CAD applications such as MicroStation and Intergraph Interactive Graphics Design System. It is used for creating and saving designs for construction projects such as highways, bridges, and buildings. The format is similar to Autodesk’s DWG file format and is considered its competitor.
Files with PPTM extension are Macro-enabled Presentation files that are created with Microsoft PowerPoint 2007 or higher versions. They are similar to PPTX files with the difference that the lateral can't execute macros though they can contain macros. PPTM files can be edited by opening them in Microsoft PowerPoint and updating the contents. Another similar format is PPSM but it is read-only by default and starts the slideshow when opened. PPTM, like PPTX, contains slides for different presentation elements like text, images, videos, graphs and other related material.
You can also convert DGN into many other file formats. Please see the complete list below.