History of Computers - Linux
Linux is a Unix-like, low-cost, open-source operating system written in C language. The Linux kernel (core of the operating system that carries out system functions) was created by a University of Helsinki student, Linus Torvalds, in 1991. Linux was originally designed for PCs based on Intel x-86 architecture, but it has since been adapted for more computer hardware platforms than any other operating system.
Overview
The Linux kernel is monolithic, meaning that all the device drivers are part of the kernel proper.
Linux has all the features of Unix and also supports the following:
- multitasking
- memory protection: so that one program can’t bring the whole system down
- multi-user usage
- multithreading: having several, independent threads of control
- virtual memory
- demand loading: only reading into RAM the parts of the program that are necessary
- copy-on-write: if more than one copy of an application is loaded, all tasks can share the same memory
- swap space: pages of memory can be written to a reserved area of a disk (the swap space) and treated as an extension of physical memory (RAM); used when the amount of physical RAM available is insufficient
Linux runs on many different CPUs (not just Intel's) and is used on a wide range of devices: servers, mainframes and supercomputers, desktops, electric keyboards, readers, etc. In fact, more than 90% of today's fastest supercomputers run some form of Linux. Linux even runs on embedded systems, in which the operating system is built into non-volatile memory (such as ROM); for example, it is used on mobile phones (the Android system is built upon the Linux kernel), tablet computers, network routers, televisions, and video game consoles.
Linux has been packaged into over 300 distributions, with about a dozen for general-purpose use; popular distributions include Debian, Fedora, Mandriva/Mageia, openSUSE, and Arch Linux.
Linux was released under the GNU General Public License and is still being developed and managed by the open source community.
Significance
Linux is significant to computer history because of its versatility (with regards to being able to run on such a wide range of devices) and because it is one of the most widely distributed open-source operating systems.
