How an Operating System help users?

Answer 1

Program execution. The operating system loads the contents (or sections) of a file into memory and begins its execution.

A user- level program could not be trusted to properly allocate CPU time.

I/O operations. Disks, tapes, serial lines, and other devices must be communicated with at a very low level.

The user need only specify the device and the operation to perform on it, while the system converts that request into device- or controller-specific commands.

User-level programs cannot be trusted to access only devices they should have access to and to access them only when they are otherwise unused.

File-system manipulation. There are many details in file creation, deletion, allocation, and naming that users should not have to perform.

Blocks of disk space are used by files and must be tracked. Deleting a file requires removing the name file information and freeing the allocated blocks.

Protections must also be checked to assure proper file access. User programs could neither ensure ad- herence to protection methods nor be trusted to

allocate only free blocks and deallocate blocks on file deletion.

Communications. Message passing between systems requires messages to be turned into packets of information, sent to the net- work controller,

transmitted across a communications medium, and reassembled by the destination system. Packet ordering and data correction must take place.

Again, user programs might not coordinate access to the network device, or they might receive packets destined for other processes.

Error detection. Error detection occurs at both the hardware and software levels. At the hardware level, all data transfers must be inspected to ensure

that data have not been corrupted in transit. All data on media must be checked to be sure they have not changed since they were written to the media.

At the software level, media must be checked for data consistency; for instance, whether the number of allocated and unallocated blocks of storage match

the total number on the device. There, errors are frequently process-independent (for instance, the corruption of data on a disk), so there must be

a global program (the operating system) that handles all types of errors. Also, by having errors processed by the operating system, processes need not contain

code to catch and correct all the errors possible on a system.

Answer 2

OS is the main stuff in computers, in fact it is the main supporting system, consider it as the main supplement for your works on a computer. for more information just Google it.