The G3 format is used to compress image files in TIFF format when sending faxes. The compression algorithm allows for the use of a standard 10-times compression, which can be increased. It is used to remove excess image data, which makes it possible to reduce the size of the image and speed up delivery.
DOT is a template file created by Microsoft Word, a word processing application. The DOT file provides a solution for situations where many similar documents with the same font and layout are required with simple changes between them needed, like names and places for example