In order for a computer to work properly, it has to contain some basic parts. A microprocessor, internal memory, data and command bus and external memory; all these components are mounted inside a computer case.
The microprocessor - it represents the brain of the computer, the coordinator of all the operations that are made. A microprocessor contains inside areas in which it can save data of short lengths. These locations are named registry, and each registry has a special name (AX, BX, etc.). From all the registry, there is one which has a special role, and that is the IP registry (Instruction Pointer). The microprocessor is connected to the other computer parts through the data bus and command bus.
The internal memory – physical, it is made out of more integrated circuits with a role in keeping the information, which have an exterior aspect that resembles with the microprocessor. The microprocessor can write or read data from the memory. Reading requires obtaining the saved information, and the writing consists in the submission of information in memory. The internal memory is made out of more parts with equal sizes, which are named memory spaces. The memory spaces are numbered in order starting with the value of 0 (0, 1, 2, 3, 4, etc.). These tags which are put over the memory spaces are named memory addresses.
The data bus and command bus – even though the name is pretentious, these buses are nothing but a bunch of wires (copper tracks on a printed circuit board). Of course, on the command bus are running the commands, and on the data bus are running the transferred data between the computer’s components. All the devices which are different than the microprocessor or the internal memory are named peripheral. The screen, the printer, are named output peripherals because the data are coming out of the internal memory and go to the devices. The keyboard is a input peripheral because the data are running backwards, from the exterior into the internal memory.
The external memory – is represented by magnetic disks, which have the property to read and write information of the magnetic support. The external memory usually has a bigger capacity than the internal ones. In the external memory are saved more programs and their corresponding data. The external memory is made out of hard drives and floppy disks. The hard drives are usually mounted inside the computer case and can be detached from the computer only by the removal of the case. The flexible disks are introduced in a particular space, are used as long as are needed, after which can be removed easily. Thanks to the constructive module, the hard drives have a very large storage capacity for the information and a very high writing speed. The hard drives are used for massive data saving or for fast program running. The flexible disks, with a smaller storage capacity, are used to transfer data between computers or to keep some important information into a safe place.
