Linux is what is known as an operating system. It is a free (open source) alternative to the comercial operating system. Linux is based on versions of the popular Unix operating systems which was developed by Bell Labs and made popular in the educational community by USC Berkley by their version which was freely ditributed to educational institions.

Linux is the brainchild of Linus Torvald who developed the orginal version as a grad school project in Finland. Since then thousands of developers around the globe have contributed to make Linux a world class operating system.

Linux itself is what is known as the kernel of the the operating system. The kernel knows how to handle input and output (I/O) devices like hard drives or serial ports and provides all of the most primative functions of the oprating enviornment.

The kernel is only part of the Linux operating enviornment. Much of the usefulness of Linux, comes from GNU (as in GNU is not Unix) utility packages. These packages are distributed by the non-profit Free Software Foundation as groups of programs that serve related functions. For exmaple, the fileutils package include ls (dir), cp (copy) and mv (rename) amongst others. Linux wouldn't be very useful without these commonly used commands. This is why Linux is often refered to as GNU/Linux.

The Linux kernel like its Unix brethern was designed from the ground up as a muti-tasking enviornment. This allows several tasks or processes (or programs) to run simultaneously. The kernel coordinates CPU, memory and I/O resources and prevents a single task from hogging resources. Each running process can have its execution priority set so some processes are allowed more resources than others. In addition, the kernel utilizes interupts, dma and timers to eliminate CPU resouce waste.