The operating system is the most significant fundamental of all the system programs, it controls all the computer's resources and provides the base upon which the application programs can be written (Tanenbaum, 1992). Therefore, it is crucial for computer users to select a robust, dependable, stable operating system, which can execute programs in a convenient and efficient manner. Linux operating system, which is widely used in recent years, has become increasingly popular in the computer world.
             The development of the Linux operating system began in 1991, when a Finnish student, Linus Torvald, wrote and christened Linux, a small but self-contained kernel for the 80386 processor, the first true 32-bit processor in Intel's range of PC-compatible CPUs (Silberschatz et al., 2003). Because Linux is free, a large number of computer users have been rapidly attracted by it. According to reasonable market estimates, there are over eight million Linux users in the world (Grace and Parker, 2000). This essay will introduce the components and characteristics of Linux and establish the causes of its popularity in comparison with other operating systems. "Linux looks and feels much like any other UNIX system; indeed, UNIX compatibility has been a major design goal of the Linux project" (Silberschatz et al., 2003, p.695). Therefore, the Linux system has the same components as UNIX, which includes kernel, system libraries and system utilities (Silberschatz et al., 2003). These three components can be seen in figure 1. Before drawing out the benefits of Linux it is necessary to understand the functions of every component.
             To begin with, 'the kernel is responsible for maintaining all the important abstractions of the operating system, including such things as virtual memory and processes'(Silberschatz et al., 2003, p.701). Thus, it is the 'heart' of the Linux system. Unlike other operating systems, the Linux source code is made available for free o...