Operating system is a computer program that manages computer hardware and software resources, and is also the core and cornerstone of computer system. Operating systems need to deal with such basic tasks as managing and configuring memory, determining the order of supply and demand of system resources, controlling input and output devices, operating networks and managing file systems. The operating system also provides an interface for users to interact with the system.
Operating system mainly includes the following functions:
(1)The main task of process management is process scheduling. In the case of single user and single task, the processor is only one task of a user, and the work of process management is very simple. However, in the case of multi-programming or multi-user, when organizing multiple jobs or tasks, it is necessary to solve the problems of processor scheduling, allocation and recycling.
(2) Storage management can be divided into several functions: storage allocation, storage sharing, storage protection and storage expansion.
(3)Equipment management has the following functions: equipment allocation, equipment transmission control, equipment independence.
(4) File management: file storage space management, directory management, file operation management, file protection.
Job management is responsible for handling any requests submitted by users.
I. Windows Operating System
Windows is an operating system under DOS proposed by Microsoft in 1985. As an operating system designed for PC and server users, its subsequent edition eventually gained the monopoly position of PC operating system software in the world. Windows operating system and its subsequent versions can run on several different types of platforms, such as personal computers, servers and embedded systems. Among them, Windows is the most popular in the field of personal computers. In November 1985, in response to the graphical user interface (GUI) trend led by Macintosh, Microsoft introduced an operating environment called Windows. At first, "Windows" was just an add-on to MS-DOS, but now Windows has developed into an independent operating system, which almost monopolizes the entire PC operating system market. At a conference on future trends held by IDC in 2004, Avneesh Saxena, vice chairman of IDC, announced that Windows had a market share of about 90% of the terminal operating system. The current client version of Windows is Windows Vista. The current server version of Windows is Windows Server 2008.
II. Android Operating System
Android is a free and open source operating system based on Linux. Mainly used in mobile devices, such as smartphones and tablets, led and developed by Google and the Open Mobile Alliance. There is no unified Chinese name yet. Android is widely used in mainland China. The Android operating system was originally developed by Andy Rubin, which mainly supports mobile phones. In August 2005, Google acquired the capital injection. In November 2007, Google formed an open mobile alliance with 84 hardware manufacturers, software developers and telecom operators to develop and improve Android systems. Then Google released Android's source code in the form of an Apache open source license. The first Android smartphone was released in October 2008. Android has gradually expanded to tablets and other areas, such as television, digital cameras, game consoles, smart watches and so on. In the first quarter of 2011, Android surpassed Symbian in global market share for the first time and ranked first in the world. In the fourth quarter of 2013, Android mobile phones had a global market share of 78.1%. On September 24, 2013, Google's operating system Android ushered in its fifth birthday. The number of devices using the system worldwide has reached 1 billion.