INSIDE THE COMPUTER Basically all computers, regardless of their size, have the same general design, which consist of the following units: CPU (central processing unit), input, storage, and output .
CPU - The main unit inside the computer is the CPU. The CPU is responsible for all events inside the computer. It controls all internal and external devices, performs arithmetic and logic operations. Central Processing Unit
Peripheral devices are devices connected to the computer but external in relation to the processing unit . If a peripheral device is disconnected, the computer will still be able to work; only functions performed by this peripheral device will not be available. Peripheral devices can reside inside the computer case or outside . Peripheral Devices
Peripheral devices are connected to the computer through ports , or sockets , that are mounted outside. Some peripherals (e.g. disk drives) are located inside the computer case, so they are connected via expansion slots . Peripheral Devices
INPUT Input devices are used to put information in your computer . The purpose of input devices is to translate data and information from human-readable format to electrical impulses . INPUT DEVICES
Storage Computers store all kinds of information. They store the information you give them, instructions from the software you're using, plus the instructions they need to operate. To store all this, they use two basic kinds of storage.
Storage RANDOM ACCESS MEMORY (RAM) Temporary storage is for information actively being used for processing. RAM's primary purpose is to temporarily store programs given to it by a programmer or operator of the computer. This type of memory is temporary because it is erased when the computer is turned off (powered down).
Storage RANDOM ACCESS MEMORY (RAM) In other words, all the information in RAM is erased when the computer is turned off. It is called random access because the processor can jump directly from one location to another in random order as the program is needed.
Storage READ ONLY MEMORY (ROM) ROM's primary purpose is to store important instructions that the computer will reuse over and over such as what to do when the computer is turned on and how to control specific requests made by the computer. ROM is permanent memory that can not be changed or erased . This is why it is called Read-Only Memory .
Storage Computers also use a variety of devices to store information that isn't actively being used for processing. Hard drives, CD-RW drives, DVD Drives, Floppy Disk Drives, Super Disk, Flash Drive and Zip Drives are all used to hold information for long periods of time until it is needed. When the information is needed, the information is taken from the drive and moved into RAM memory where the computer can access it for processing.