This format is used to compress TIFF images when sending them via fax machines. This format helps reduce the data transmission time. Group 3 eliminates redundant data during compression in order to reduce file size. The standard 10:1 compression ratio may be increased to the user's preferences, but it can lead to a significant loss of image quality.
This format is a vector images file in the Sketch Drawing program, which serves to edit and create interface designs, applications and software shells. SK-files contain objects and layers which can be edited independently of each other.