Operating systems are the programs that run in the background of computers. They manage hardware components such as memory keyboards, file-systems, file-systems monitors and printers. It also controls access to the central processing unit or CPU.
Multitasking is the term used to describe a technique that allows multiple programs to run concurrently on an OS. This is possible because the OS allocates system resources like memory space and CPU time to a program throughout execution. It tracks the program’s use of these resources and ensures that the program doesn’t interfere with other programs that are using these same resources.
Operating systems also monitor the locations and status of the files on the hard drives of the computer. They create virtual directories and store metadata, including the date of creation or modification. An OS also makes it possible for an application to connect to the hardware of a computer via drivers. These drivers translate the proprietary language of the hardware into a standard that an operating system understands.
If an application needs to save a document it switches over to the kernel of the operating system. This is because the application cannot directly connect to the disk drive, and therefore requires an interface driver to communicate with it. The operating system then creates and translates the file request into a rational operation, and then the hardware is used as instructed.