Process management is one of the most important and relevant tasks in operating syste.

Process:-In operating systems, process is defined as “A program in execution”.Process can be considered as an entity that consists of a number of elements, including: identifier, state, priority, program counter, memory pointer, context data, and I/O request.Components of process are:-

Operating system is a collection of software programs and it is responsible for the management and coordination of activities and the sharing of the limited resources of the computer.The operating system acts as an interface between an application and the hardware.The operating system is a set of services which simplifies development of applications. Executing a program involves the creation of a process by the operating system.

Techniques of File Organization

The three techniques of file organization are:

1. Heap (unordered)
2. Sorted
   1. Sequential (SAM)
   2. Line Sequential (LSAM)
   3. Indexed Sequential (ISAM)
3. Hashed or Direct

In addition to the three techniques, there are four methods of organizing files. They are sequential, line-sequential, indexed-sequential, inverted list and direct or hashed access organization.

Memory is divided into number of fixed size blocks called Frames. The virtual address space or logical memory of a process is also broken into blocks of the same size called pages. When a program is to be run, its pages are loaded into any frame from the disk. Mapping is done thru Page Map Table which contains the base address of each page in physical memory. Hardware support is given to paging using Page Map Table Register (PMRT) which will be pointing to beginning of the PMT. Look side memory or Content addressable memory is used to overcome the problem of PMT.

• Memory Management
• File organization
• Disk Space Management
• Process Management
• User Management
• Security And Network 

OS is system software, which may be viewed as collection of software consisting of procedures for operating the computer & providing an environment for execution of programs. It’s an interface between user & computer. E.g DOS is an operating system which provides command line for uses where users can enter commands.al output from computer is aso displayed in command line.

Types of Processing:

1. Serial Processing
2. Batch Processing
3. Multiprogramming.