Mac OS X comes with great applications, and a trip to the Apple Store or VersionTracker (http://www. versiontracker .com/) can bag you quite a few more. But there's a flood of new applications coming to your Mac OS X system because of its Unix core . Many of these are applications that have been around for a long time, and many are flowing in from other members of the Unix family, including Linux and FreeBSD. X11 is a terrific example: it's a graphical interface for Unix that's been around a long, long, time. Although the Mac OS X user interface is fantastic, there are many powerful Unix programs that require X11, but Apple's on top of it: Mac OS X 10.3 (Panther) includes X11 in the distribution. Read on to learn more about how you can use X11 on Mac OS X.
For typical Mac applications, freeware, shareware, or commercial, they're a breeze to install, thanks to the Mac OS X Installer. Unix applications don't have the same easy interface, but a team of dedicated programmers have created the next best thing, a powerful software distribution and installation system called Fink. Later in this chapter, we'll look at Fink, a project that makes it easy to add a vast amount of open source software to Mac OS X.