Operating Systems are all around us, we use them everyday without knowing, you can find Operating Systems in items such as :

• Consoles (Xbox 360, Ps3, Wii, PSP)

• SATNAV’s

• Mobile Phones (Andriod, Apple, Blackberry’s)

• Cars

• Computers

The main function of the Operating System is to interact with all the hardware elements of your computer.

The Main Functions of the OS are:

Processor ManagementMemory ManagementDevice ManagementStorage ManagementUser Interface

This controls the planning and process of an activity, it also monitors the performance of a process. The managing processor comes down to two related issues, it has to ensure that each application/process receives enough of the processors time to work properly. The processor can only every do one thing at one time so the operating system is in charge or sending tasks to the processor.

Data is put out in order, or for example in a line, normally as first come first serve, so it outputs data in the order it arrived. A Buffer temporarily holds data (Queues it up) before moving it onto another place. Data is stored in the buffer as it is retrieved from an input device or sent to an output device e.g. Mouse or speakers.

Memory management is the act of managing computer memory, this involves providing ways to allocate portions of memory to programs at their request, and freeing the memory for other programs to reuse when no longer needed. The management of main memory is critical to the computer system.

Device management on a computer is accomplished through the operating system, motherboard and drivers. A driver helps the operating system communicate with the electrical signals from computer hardware.

A Device Driver or software driver is a computer program which converts the messages from the Operating system into messages that the hardware device can understand.

File Management organises your documents/programs in a well organised filing system, say for instance if application is downloaded or a Microsoft word document has been written/changed it will be saved to a destination of your choice.

User interface is where a Human interacts with machines. The user interface includes hardware and software which exist for various systems, and provide a means of input/output.

User interfaces Allow the user to interact much easier in ways such as the desktop icons (shortcuts) taking you to files within files making getting to them files much more easier.

The Operating System has the role of Swapping commands in and out, it can switch between processes thousands of times per second.

Virtual Memory is where if your computer lacks the RAM needed to run a programme/operation, the Operating system uses virtual memory to compensate for the needed memory.

Virtual Memory combines your RAM with the temporary space on your HDD, So when there isn't enough space on the RAM the Virtual Memory moves the data to a temporary storage destination (paging file).

A File Allocation Table is a computer file system architecture now commonly

used on a substantial amount of computers, memory cards and floppy

disks.