A big part of the Linux operating system as most people know it, has little if anything to do with what Linux really is at it's roots. Linux really is just the kernel and drivers, but the biggest part of what most people consider to be Linux is the applications. GNU applications make up almost everything you'll learn about as a Linux user. Even the guts of the GUI display you log into is really nothing more than an application running on your Linux machine. Coming from the Window$ world it is hard to make the distinction between the Desktop and the operating system... in Linux they are totally seperate beasts, in fact, almost every Linux server you see won't be running any kind of desktop at all. The distinction is so apparent that if you watch the application log while do something as basic as bringing up your network card, you can see that a small program gets executed to go out and request a DHCP address for you. In turn, you can look at the man page for this little application to figure out it's options and handle executing this program manually if you'd like. This sounds silly, but you might have some special requirement that the normal invocation of this application won't handle. This idea of small focused applications surrounding a specialzed kernel affords you this kind of granularity of power and it makes it easier for developers to debug and maintain these tools. The overall effect seems to be a more manageable and extensible software platform.