Operating System

An operating system (OS) is system software that manages computer hardware and software resources and provides common services for computer programs. All computer programs, excluding firmware, require an operating system to function. Time-sharing operating systems schedule tasks for efficient use of the system and may also include accounting software for cost allocation of processor time, mass storage, printing, and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and frequently makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computer – from cellular phones and video game consoles to web servers and supercomputers. The dominant desktop operating system is Microsoft Windows with a market share of around 82%. OS X by Apple Inc. is in second place (9.8%), and Linux is in third position (1.5%). In the mobile (smartphone and tablet combined) sector, based on Strategy Analytics Q3 2016 data, Android by Google is dominant with 87.5 percent or growth by 10.3 percent in one year and iOS by Apple is placed second with 12.1 percent or decrease by 5.2 percent in one year, while other operating systems amount to just 0.3 percent. Linux is dominant in the server and supercomputing sectors. Other specialized classes of operating systems, such as embedded and real-time systems, exist for many applications.

Microsoft Windows (or simply Windows) is a metafamily of graphical operating systems developed, marketed, and sold by Microsoft. It consists of several families of operating systems, each of which cater to a certain sector of the computing industry with the OS typically associated with IBM PC compatible architecture. Active Windows families include Windows NT, Windows Embedded and Windows Phone; these may encompass subfamilies, e.g. Windows Embedded Compact (Windows CE) or Windows Server. Defunct Windows families include Windows 9x; Windows 10 Mobile is an active product, unrelated to the defunct family Windows Mobile. Microsoft introduced an operating environment named Windows on November 20, 1985, as a graphical operating system shell for MS-DOS in response to the growing interest in graphical user interfaces (GUIs). Microsoft Windows came to dominate the world's personal computer (PC) market with over 90% market share, overtaking Mac OS, which had been introduced in 1984. Apple came to see Windows as an unfair encroachment on their innovation in GUI development as implemented on products such as the Lisa and Macintosh (eventually settled in court in Microsoft's favor in 1993). On PCs, Windows is still the most popular operating system. However, in 2014, Microsoft admitted losing the majority of the overall operating system market to Android,because of the massive growth in sales of Android smartphones. In 2014, the number of Windows devices sold were less than 25% of Android devices sold. This comparisons, however, may not be fully relevant as the two operating systems traditionally targeted different platforms. Click here to learn how to install Microsoft windows 7.

Linux is a Unix-like computer operating system assembled under the model of free and open-source software development and distribution. The defining component of Linux is the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. The Free Software Foundation uses the name GNU/Linux to describe the operating system, which has led to some controversy. Linux was originally developed for personal computers based on the Intel x86 architecture, but has since been ported to more platforms than any other operating system.[18] Because of the dominance of Android on smartphones, Linux has the largest installed base of all general-purpose operating systems.[19] Linux is also the leading operating system on servers and other big iron systems such as mainframe computers and on 99.6% (including top 385) of the fastest (TOP500) supercomputers, but is used on only around 2.3% of desktop computers; not including Chrome OS, used in Chromebooks, that are dominating the US K–12 education market, while overall in the US are at about 5% and representing nearly 20% of the sub-$300 notebook sales. Linux also runs on embedded systems, which are devices whose operating system is typically built into the firmware and is highly tailored to the system; this includes smartphones and tablet computers running Android and other Linux derivatives, TiVo and similar DVR devices, network routers, facility automation controls, televisions, video game consoles and smartwatches. Click here to learn how to install ubuntu.