GEM Metafiles are vector graphic files which include drawing commands for rendering pictures. They are similar to, but less complete than CGM files. GEM files originated on the Amiga, and have gone through several enhancement periods.
ThumbsPlus does not claim to support all GEM files at this time; fonts are not handled very well, and curve support is incomplete. However, the support is sufficient for most clip-art, the most common type of file stored in GEM format.