1. Operating Systems Overview Basic Computer Concepts Operating System What does an operating system do  A computer’s software acts similarly with the chain of command in an army. Using application software, you issue a command. Application software tells the operating system what to do. The operating system instructs the device drivers, device drivers instruct the hardware and the hardware actually does the work.

2. Operating Systems Overview Basic Computer Concepts Operating System What does an operating system do  The operating system interacts with application software, device drivers, and hardware to manage a computer’s resources. While interacting with application software, operating system is busy behind the scenes with other tasks.

3. Operating Systems Overview Basic Computer Concepts Operating System How does an operating system affect the “look and feel” of application software?  An operating system typically provides user interface tools, such as menus and toolbar buttons, that define the “look and feel” for all of its compatible software. Apple computer released its popular Macintosh computer in 1984, which featured a GUI operating system and applications. During 1992, when Windows 3.1 became standard issue on most PCs, GUIs did catch on in the PC market, replacing a command-line interface that had given many people a string aversion to computers in general.

4. Operating Systems Overview Basic Computer Concepts Operating System Where is the operating system  The entire operating system is small enough to be stored in ROM for typically handheld computers and video game consoles. For nearly all personal computers, servers, workstations, mainframes, and supercomputers, the operating system program is quite large, so most of it is stored on a hard disk. The bootstrap program provides the instructions needed to load the core parts (kernel) into memory when the system boots. Customization utilities and other parts of the operating system are loaded into memory as they are needed.

5. Operating Systems Overview Basic Computer Concepts Operating System Do I ever interact directly with the OS Launch programs Customize the user interface Manage Files Configure Equipment Get Help

6. Operating Systems Overview Basic Computer Concepts Operating System Are different operating systems needed for different computing tasks ?  Single-user operating system  deals with one set of input devices, those that can be manipulated by one user at a time  Multi-user operating system  deals with input, output, and processing requests from many users, all at the same time

7. Operating Systems Overview Basic Computer Concepts Operating System Are different operating systems needed for different computing tasks?  Network operating system  provides communications and routing services that allow computers to share data, programs and peripheral devices  Multitasking operating system  provides process and memory management services that permit two or more programs to run simultaneously

8. Operating Systems Overview Basic Computer Concepts Operating System Are different operating systems needed for different computing tasks  Desktop operating system  designed for a personal computer, either a desktop or notebook computer designed to accommodate a single user, but may also provide networking and multitasking capabilities

9. Operating Systems Overview Basic Computer Concepts Windows, MAC OS, Linux, UNIX and DOS What’s the best-selling operating system?

10. Operating Systems Overview Basic Computer Concepts Windows, MAC OS, Linux, UNIX and DOS Is Mac OS similar to Windows?  Both operating systems base their user interfaces on the graphical model that was originated at Xerox PARC, although Mac OS was developed several years before Windows Mac and Windows interfaces use a mouse to point and click various icons and menus Are UNIX and Linux the same?  UNIX, developed in 1969 at AT & T’s Bell Labs, gained a good reputation for its dependability in multi-user environments Linux was developed in 1991, based on a version of the UNIX kernel called Minix Linux is considered to be a popular operating system for e-mail, web-servers and local area networks

11. * Property of STI Page 11 of 1 Operating Systems Overview Basic Computer Concepts Windows, MAC OS, Linux, UNIX and DOS Why do I keep hearing about DOS?  stands for Disk Operating System it provides part of the operating system kernel for Windows versions 3.1, 95, 98 and ME users rarely interact with DOS, because it is well hidden by the Windows graphical user interface