Subcategories:
You can see the full category hierarchy on the Category Map.
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| 2 beginning with A  | AIR (2) APOLLO  | 
| 5 beginning with B  | BAMBOO BEOWULF BILTMORE BLUECURVE BLUECURVE (2)  | 
| 1 beginning with C  | CD-ROM (2) | 
| 3 beginning with D  | DARL DEBIAN DOLPHIN  | 
| 1 beginning with E  | ENIGMA | 
| 2 beginning with G  | GUICIDE (2) GURU (2)  | 
| 2 beginning with H  | HEDWIG HURRICANE  | 
| 1 beginning with I  | IBOOK (5) | 
| 1 beginning with K  | KOPERNICUS | 
| 4 beginning with L  | LAPTOP (4) LINUS TORVALDS LINUX LINUX (2)  | 
| 1 beginning with N  | NOVELL | 
| 1 beginning with P  | PICO | 
| 2 beginning with R  | RAWHIDE RED HAT (2)  | 
| 8 beginning with S  | SCO SEAWOLF SHRIKE SID SID (2) SID (3) SLACKWARE SUSE  | 
| 2 beginning with U  | USL USL (2)  | 
| 4 beginning with XYZ  | XFREE XFREE (2) YARROW YAST  | 
40 apronyms in total | |