- UNIX is a registered trademark of The Open Group.
- FREENIX is a trademark of Applied Digital Arts.
- Linux is a Registered Trademark of Linus Torvalds.
- UnixWare and OpenServer are trademarks of Santa Cruz Operation.
- Tru64 is a trademark of Compaq.
- AIX is a trademark of International Business Machines Corporation.
- Solaris is a trademark of Sun Microsystems.
- NetBSD is a free, highly portable UNIX-like operating system available for many platforms.
- HP-UX is a trademark of Hewlett-Packard Co.
- IRIX is a trademark of Silicon Graphics, Inc.
- U/WIN is a trademark of Global Technologies Ltd., Inc.
- A/UX and Mac OS X are trademarks of Apple Computer.
- Free BSD and BSD/OS are trademarks of BSDi.
- Minix is a Unix-like freely distributed operating system.