State four types of Operating System

2. State four types of Operating System

Real-time operating system

(RTOS) - Real-time operating systems are used to control machinery, scientific instruments and industrial systems. An RTOS typically has very little user-interface capability, and no end-user utilities, since the system will be a "sealed box" when delivered for use. A very important part of an RTOS is managing the resources of the computer so that a particular operation executes in precisely the same amount of time, every time it occurs. In a complex machine, having a part move more quickly just because system resources are available may be just as catastrophic as having it not move at all because the system is busy.

Single-user, Single task

As the name implies, this operating system is designed to manage the computer so that one user can effectively do one thing at a time. The Palm OS for Palm handheld computers is a good example of a modern single-user, single-task operating system.

Single user, Multi-tasking

This is the type of operating system most people use on their desktop and laptop computers today. Microsoft's Windows and Apple's MacOS platforms are both examples of operating systems that will let a single user have several programs in operation at the same time. For example, it's entirely possible for a Windows user to be writing a note in a word processor while downloading a file from the Internet while printing the text of an e-mail message.

Multi-user

A multi-user operating system allows many different users to take advantage of the computer's resources simultaneously. The operating system must make sure that the requirements of the various users are balanced, and that each of the programs they are using has sufficient and separate resources so that a problem with one user doesn't affect the entire community of users. Unix, VMS and mainframe operating systems, such as MVS, are examples of multi-user operating systems.

It's important to differentiate between multi-user operating systems and single-user operating systems that support networking. Windows 2000 and Novell Netware can each support hundreds or thousands of networked users, but the operating systems themselves aren't true multi-user operating systems. The system administrator is the only "user" for Windows 2000 or Netware. The network support and all of the remote user logins the network enables are, in the overall plan of the operating system, a program being run by the administrative user.

With the different types of operating systems in mind, it's time to look at the basic functions provided by an operating system.

Comments

2.1.4 Distinguish between logical I/O and physical I/O

2.1.4 Distinguish between logical I/O and physical I/O logical input relate to hard disk Logical I/O an Physical I/O Physical" I/O is an actual fetch of data from a storage device such as a disk. Logical" I/O is a programmatic request for data satisfied by a memory (block, buffer) access. A logical I/O may cause a physical I/O in the first place, or a logical I/O may retrieve a part of a block (buffer) of data from memory. 2.1.5 Distinguish between directory management and disk space management. Directory management A directory is a hierarchical collection of directories and files. The only constraint on the number of files that can be contained in a single directory is the physical size of the disk on which the directory is located. Disk management A hard disk is a rigid disk inside a computer that stores and provides relatively quick access to large amounts of data. It is the type of storage most often used with Windows. The system also supp

3.1.1 Identify Between Resident And Transient Routines

Memory Management Memory management is concerned with managing: The computer’s available pool of memory Allocating space to application routines and making sure that they do not interfere with each other. 3.1.1 Identify between resident and transient routines The operating system is a collection of software routines. Resident routines Transient routines Routines that directly support application programs as they run Stored on disk and read into memory only when needed Example: routine that control physical I/O Example: routine that formats disks The operating system occupies low memory beginning with address 0. Key control information comes first followed by the various resident operating system routines. The remaining memory, called the transient area, is where application programs and transient operating system routines are loaded. Resident & transient routines structure

Operating Systems Definition and the Classification of OS

OPERATING SYSTEMS ( OS ) What is an operating system? An operating system (sometimes abbreviated as "OS") is the program that, after being initially loaded into the computer by a boot program, manages all the other programs in a computer. The other programs are called applications or application programs. The application programs make use of the operating system by making requests for services through a defined application program interface (API). In addition, users can interact directly with the operating system through a user interface such as a command language or a graphical user interface (GUI). An operating system performs these services for applications: In a multitasking operating system where multiple programs can be running at the same time, the operating system determines which applications should run in what order and how much time should be allowed for each application before giving another application a turn. It manages the sharing of

learningoperatingsystem

Search This Blog