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.
CUR is a file - the image of the cursor, sometimes animated, which is used for the mouse pointer in Windows. This may be an arrow (for general use), rotating hourglass (wait), or the symbol I (editing). Users can change or edit the standard cursors. To view and edit files .CUR suitable programs such as Inkscape, Corel VideoStudio.