Computers very basics Part-3

Operating system

Operating system is a software and is the interface between user and computer hardware. The primary goal of an operating system is to make the computer system convenient to use the computer hardware in an effcient manner.

Operatin system services

The operating system can handle the following services.

(i) I/O handling: A running program may require input and output from teh user. This will be handled by operating system.

(ii) Program execution: Whenever a suer had to execute a program, ti shound be loaded onto the memeory and executed from there and after that it is terminated. This will be done by the operating system.

(iii) File handing: Wherever date had to be stored in a permanent fro, it should be stored in a file. The operating system stores the data on the desk and maintains a table where the date file is saved.

(iv) Error detection: Errors can occur due to hardware, I/O, memeroy etc and the program. The operating system has consistent way to handle these errors.

(v) Accounting: Operating system has to provide accounting services where the various resources utilisation is maintined so that the system time required fro a job can be calculated and the result used fro fine tuning its performance at a later time.

OPERATING SYSTEM INTERFACES

The screen items use see and interact are defined as user interaces. there are different types of interfaces. We will discuss each of them.

Character based intereces

The best example for character based interface operating system is Disk Operating System (DOS). This is used in the priliminary stages of a computer. this will display only a fixed set of character like letters A to Z, a to z, the numbers 0-9 and special symbols like @,#,$,%,^,&, etc.