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.
A file with the DOCM file extension is a Word Open XML Macro-Enabled Document file used in Microsoft Word. It was introduced in Microsoft Office 2007. DOCM files are just like DOCX files except that they can execute macros, which lets you automate repetitive tasks in Word.