What Is An Operating System?
An operating system is a program that controls the normal functions of your computer. There are two mainstream operating systems today – Windows and MacOS. There are different versions of both operating systems, and it is important to determine which one you have before we can assist you. If you have a Macintosh, go to the Finder (or click on the desktop in OS X). Select the Apple Menu, and choose About This Macintosh or About This Computer. The operating system version your computer is running will be displayed on the window that pops up. Mac OS X versions include 10.0, 10.1, 10.2, 10.3, 10.4 and 10.5. If you have a PC, chances are you are running some form of Windows. If your computer starts up with a splash screen that says “Windows Vista” and have a round Start Button, then you are running Windows Vista. Other versions of Windows, identified by their splash screens, include Windows 98, Windows NT, Windows 2000, Windows Me, and Windows XP. Click here to return to the Get Help form.
From the DOJ v. Microsoft trial “Findings of Fact”, issued by Judge Thomas Penfield Jackson on November 5, 1999: An ‘operating system’ is a software program that controls the allocation and use of computer resources (such as central processing unit time, main memory space, disk space, and input/output channels). The operating system also supports the functions of software programs, called “applications,” that perform specific user-oriented tasks. The operating system supports the functions of applications by exposing interfaces, called ‘application programming interfaces,’ or ‘APIs.’ These are synapses at which the developer of an application can connect to invoke pre-fabricated blocks of code in the operating system. These blocks of code in turn perform crucial tasks, such as displaying text on the computer screen. Because it supports applications while interacting more closely with the PC system’s hardware, the operating system is said to serve as a ‘platform.’ Source: http://usvms.g
