Explain the purpose of an operating system
A multitasking operating system may give the appearance that a lot of processes are running concurrently/simultaneously, this is not true as only one process can be executing at any one time on a single-core CPU, unless on a multi-core or similar technology. Processes are often called tasks in embedded operating systems. The function of the task or process is something that takes up time, as opposed to memory, which is 'something that takes up space or capacity For security and reliability reasons most modern operating systems prevent direct communication between independent processes, providing strictly mediated and controlled inter-process communication functionality.
This involves providing ways to allocate portions of memory to programs at their request, and freeing it for reuse when no longer needed. The management of main memory is critical to the computer system. Virtual memory systems separate the memory addresses used by a process from actual physical addresses, allowing separation of processes and increasing the effectively available amount of RAM using paging or swapping to secondary storage. The quality of the virtual memory manager can have a big impact on overall system performance. Processes should not be able to source the memory for another process without permission. This is called memory protection, and prevents malicious or malfunctioning code in one program from interfering with the operation of other running programs.
Basic storage involves dividing a disk into primary and extended partitions. This is the way that all versions of Windows that were reliant on DOS-handled storage took, and disks formatted in this manner are known as basic disks. Dynamic storage involves the use of a single partition that covers the entire disk, and the disk itself is divided into volumes or combined with other disks to form volumes that are greater in...
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