Computer operating system.

 

Computer operating system.

An operating system (OS) is the software that controls all of the other application programs on a computer once it has been first loaded by a boot program. The application programs utilize the operating system by submitting service requests via a specified.

Application program interface (API): An operating system is a program that manages how application programs are executed and serves as a conduit between a computer's hardware and its user.

According to a more widely accepted definition, the operating system is the only program that runs continuously on the computer; all other programs are application programs. This program is typically referred to as the kernel.

Allocating resources and services, such as memory, data, devices, and processors, is the main duty of an operating system. The operating system has several programs to manage these resources, including a scheduler, memory management module, traffic controller, I/O programs, and file system.

Need for an Operating System:

• The primary need for the OS arises from the fact that user needs to be provided with services and OS ought to facilitate the provisioning of these services. 
  
  
• The Control processing unit (CPU)  is the most important  part of a computer system. A system should allow the processing unit to be used by a user's application.
  
  
• Information would need to be stored in a user application. When an application needs memory, the operating system makes it available. In a similar vein, user apps require input facilities in order to interact with one another.
  
  
• Usually, this takes the shape of a keyboard, mouse, or even a joystick (for example, if the application is a game). 

Booting Process in an Operating System.

Our computer may be turned on by software commands, a button pro, or other hardware, or by its central processing unit. Because the CPU lacks any software in its math memory, there is a procedure that must first load the software into main memory before it may run. 

There are followings six steps:

Step 1: BIOS (Basic Input Output System) conducts a sequence of operations or functional tests on stored programs after the computer system is switched on. The system performs a self-test upon power-on (POST), which is stored in ROM, to determine if the system's peripherals are functioning properly.

Step 2: After the BIOS completes pre-boot operations or a functional test, it reads the bootable sequence from CMOS (Common Metal Oxide Semiconductor) and checks. according to the CMOS boot device sequence, for the master boot record located in the first physical sector of the bootable disk. For instance, if the boot device sequence is: Floppy Disc, hard drive, CD-ROM.

Step 3: The master boot record will next look in a floppy disk drive. If the master boot record is missing, the hard drive will look for it. However, the CDROM drive will search for the master boot record if it's not even on the hard drive. If the ROM cannot read the master boot record from any of these sources, it displays "No boot device found" and turns off the computer. Once the master boot record is found, the operating system loader—also known as the Bootstrap loader—is loaded from a specific bootable disk drive. The boot sector of a bootable device contains a program called a bootstrap loader.

Step 4: The bootstrap loader loads the IO.SYS file first in step 4. The essential file of the DOS operating system, MSDOS.SYS, is then loaded.

Step 5: The MSDOS.SYS file then looks for the Command Interpreter in the CONFIG.SYS file and loads it into memory once it has located it. If the CONFIG.SYS file does not specify a default Command Interpreter for the DOS operating system, the COMMAND.COM file loads as such.

Step 6: The final file to be loaded and run is the AUTOEXEC.BAT file, which has a list of DOS commands. The prompt is then shown. The computer system shows the drive letter of the bootable drive, proving that the operating system has booted successfully from that drive.

Features of operating system:

1. The connection between the computer's hardware and software is known as the operating system. All of the computer's resources and functions are managed by this vast collection of specialized programs.
   
   
2. All other computer programs, including ramp and other system application applications, are managed and their performance monitored by this specialist software. software. As the name suggests, an operating system is software that is necessary for a computer to function.
   
   
3. It serves as a mediator or intermediary between your computer's hardware and application programs. Computer software that lacks a means of connecting to the hardware.
   
   
4. In addition to this, it also serves as a mediator between the computer hardware and the user because it offers a common user interface that may be seen. after turning on your computer, you will see it on your monitor.
   
   
5. The Windows and the Mac OS are additional examples of operating systems that give users the ability to use a graphical interface with icons and images. have access to many programs and files at once.
   
   
6. Therefore, a program or software that the operating system permits users to use may utilize the System to run the eating system itself, other programs, or apps. We can say Scenes Suppose your computer operates behind the Salto run.

Characteristics of operating system:

(1) Memory Management: Keep track of the main memory, including its usage, unused areas, etc. and allots RAM in response to requests from programs or processes.

(2) Processor Management: Assigns the processor (C.P.U.) to a process and releases the processor when it is no longer needed.

(3) Device Management: Maintains a record of every device. The I/O Controller, which chooses which process has access to the device, at what moment, and for what duration, is another name for this.

(4) Mana file management and de-allocation: Handles resource allocation and file management. The dean makes the decision on who receives them.

(5) Security: Uses passwords and other comparable methods to block and prevent unapproved access to data and programs.

The goals of an operating system:

1. One of the goals of the operating system is to make things easy to use.
   
   
2. To enhance the computer system's user experience.
   
   
3. To keep the specifics of the hard ware resources hidden from the users.
   
   
4. To give users a simple way to interact with the computer system.
   
   
5. To serve as a bridge between the hardware and its users, facilitating user access to and use of additional resources.
   
   
6. To oversee a system's resources.
   
   
7. To monitor who is using what, settle competing resources, approve requests for resources, and differentiate between users and programs that are in conflict.
   
   
8. To ensure a fair and effective distribution of resources between programs and users.