Linux is a free software operating system (it is not owned by any person or company), therefore it is not necessary to buy a license to install and use it on a computer. It is a multitasking, multi-user system, compatible with UNIX, and provides a command interface and a graphical interface, which makes it a very attractive system with great prospects for the future.
Being free software, the source code is accessible so that any user can study and modify it. The Linux license does not restrict the right of sale, so various commercial software companies distribute versions of Linux. Besides this, this system has many distributions and window managers for the graphical environment.
The Linux operating system was developed by Linus Torvalds, and is based on the Minix system, which in turn is based on the Unix system, Torvalds added tools and utilities to it, making it operational. Starting with the first version of Linux, the system has been modified by thousands of programmers around the world, under the coordination of its creator.
The name of Linux comes from the name of its author Linus and the UNIX operating system. However, its real name is GNU / Linux, since the system is distributed under the GNU GPL (General Public License).
The Linux structure is based on a hybrid microkernel that executes the most basic services of the operating system. The kernel is the core of the system; the part that interacts directly with the hardware, managing all its resources, such as memory, microprocessor, peripherals, etc.
In addition, it has a program that isolates the user from the kernel, known as Shell or command interpreter, its function is to interpret the commands or applications that the user sends to the system, from a terminal in text mode or from a graphical environment, and translate them into instructions that the operating system understands.
Depending on its version, this operating system is used in supercomputers and servers such as personal computers. The different variants of Linux are called distributions, among the best known are Red Hat-Fedora, Suse, Debian, Ubuntu, and Mandriva.
Each Linux distribution distributes the kernel through operating system updates. Each version of the kernel can be distinguished by 3 or 4 numbers separated by dots. The meaning of each number is as follows:
1. Kernel version; it varies if there is a major modification in the kernel code.
2. Major revision of the kernel.
3. Minor revision, such as the inclusion of new drivers or some new features.
4. Corrections of errors or security flaws within the same revision.
Linux has come a long way in recent years, adding improvements in graphical user interfaces, and in the recognition and use of hardware resources. Little by little it is gaining ground on Windows and Unix, it has become the favorite of computer users and expert businesses (companies such as IBM or Hewlett-Packard) who consider it a robust and low-cost alternative compared to the others. operating systems; and they provide the corresponding technical support, usually as part of the server systems.