Brian Proffitt is a known OS geek who works with OS X, Linux, and Windows. He has written several books on all three of these operating systems. Brian is the Managing Editor of the popular Linux Today and Linuxplanet Web sites. A private pilot, Brian enjoys working at home and spending tune with his wife and daughters. William von Hagen is a long-tune Unix, Mac, and Linux lover who has written books on Linux, SGML, and Filesystems. He has been a Unix sysadmin for over 20 years and a Mac lover since 1984. In his spare time, Bill collects workstations and microcomputers and owns over 200 systems.