Examples of popular modern operating systems include Android, BSD, iOS, Linux, Mac OS X, Microsoft Windows,[3] Windows Phone, and IBM z/OS. All these, except Windows and z/OS, share roots in UNIX.
1 . process mangment
Process management is an integral part of any modern day operating system (OS). The OS must allocate resources to processes, enable processes to share and exchange information, protect the resources of each process from other processes and enable synchronisation among processes. To meet these requirements, the OS must maintain adata structure for each process, which describes the state and resource ownership of that process, and which enables the OS to exert control over each process.
2. memory mangment
Memory management is the act of managing computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and freeing it for reuse when no longer needed. This is critical to the computer system.
Several methods have been devised that increase the effectiveness of memory management. 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 an extensive effect on overall system performanc
3 proctection
Computer security is information security as applied to computers and networks.
The field covers includes all the processes and mechanisms by which computer-based equipment, information and services are protected from unintended or