It is
used when we can’t directly communicate with computer. In this each user prepare his program offline and submits them to computer operator. The computer
operator clicks the program which have been punched on cards and stack them
together.
When a
batch of programs has been collected the operator feeds this program to the
computer with the help of card reader. The card reader reads the program one by
one into computer memory which is then executed by CPU (central processing
unit) and the result is send to the printer.
This
processing is also called SERIAL SEQUENTIAL or STACK PROCESSING
In this
system the programs are processed one after another and there is no user
interaction during program processing.
In this
operating system we use the concept of spooling
(It is
the process of keeping all data that
comes from an input device or goes to the output device on either a magnetic
disk or a magnetic tape )
The speed
of magnetic disk is fast as compared to the speed of different input/output
devices. So, it takes less time to load program into memory and to sent the
output from memory.
In this
system if the program once loaded will remain memory until its execution is
complete. When there is only one program in main memory two of the systems most
powerful sources i.e. main memory and CPU are being utilized.
So, in
order to overcome under utilization of CPU and memory we use the concept of MULTI-PROGRAMMING OS
( In
Multi-programming OS more than one program can be loaded into computer’s memory
at the same time. When one program is performing input or output operation the
CPU can shift to the next program this leads to increase till overall speed of
execution).
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