What is Linux?
Linux is an open-source “UNIX-like” operating system, with many similarities to proprietary UNIX operating systems like Sun Microsystem’s Solaris and Hewlett Packard’s HP-UX. The Linux kernel and many applications included in Linux distributions are developed by countless programmers worldwide. This “many eyes” approach to software development arguably results in more secure and robust code, especially with high-profile projects such as the Linux kernel, KDE, Mozilla Firefox, and OpenOffice.org. Most of the software included in a Linux distribution, including the Linux kernel, is licensed under the GNU General Public License, permitting others to examine, modify, and create derivative works from the code for both commercial and noncommercial purposes.
To be technically correct, Linux is an operating system kernel, and is not itself a complete operating system. Linux distributions such as Red Hat, Fedora, SuSE, Debian, Mandrakelinux, Slackware, and Gentoo package the Linux kernel along with application software to provide a complete operating system.
The kernel, or “heart” of an operating system, is low-level software that provides an interface to system hardware. Process management, memory management, networking, multi-tasking, and disk input/output are all functions of an operating system kernel.
What began as a hobbyist project in 1991 by Finnish programmer Linus Torvalds, Linux is now a serious contender in the enterprise server market, and because of full-featured desktop environments like KDE and GNOME, Linux is slowly gaining market share in the corporate and public sector desktop market.
What are some benefits of using Linux?
One of the key benefits of using Linux is cost: most Linux distributions are available at no charge. UNIX administrators can transition to Linux with ease; Windows adminstrators may require re-training to the UNIX “way of doing things.” Therefore, the Total Cost of Ownership (TCO) of a Linux-based solution is not always lower than a Windows or proprietary UNIX-based solution. However, many companies have saved millions of dollars deploying Linux.
If vendor support is required, companies such as Red Hat offer enterprise Linux distributions. For example, Red Hat’s enterprise offering–Red Hat Enterprise Linux (RHEL)–has an 18-month “enterprise-friendly” release cycle, provides five years of security and “bug fix” updates, and offers telephone and Web-based technical support.
Linux excels as a server platform, particularly because of Linux’s rock-solid stability. Linux is well-suited for firewalls, file and print servers, DNS servers, mail servers, cache servers, application servers, and database servers.
In recent years, Linux has made significant strides in desktop usability. Linux distributions typically include the KDE and GNOME desktop environments, providing similar look-and-feel and functionality to Microsoft Windows and Mac OS X.