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Categorizing Computer Hardware based on Processing, Memory, I/O, Storage, Bus Interconnection

Computer Hardware Categories

The computer is essentially comprised of the same basic hardware

Hardware may be categorized into five types

1. Processing Devices
2. Memory Devices
3. Input and Output Devices
4. Storage Devices
5. Bus interconnection

Processing Devices

• The Process whereby you convert raw data into meaningful information is called processing
• Processor may be seen as the brain of the computer as it carries out the instructions received from user or the program
• Central Processing Unit (CPU)
  • Performs arithmetic and logical operations.
  • Manpulates the data and converts it into useful.
• Processor chips made of silicon and copper
• It may be the case that a computer has more than one processor
• The motherboard is a firm rectangle shaped card that contains the circuitry that connects the processor to others hardware compnents.
• Internal devices such as cound cards, video cards, disk controllers may be mounted on circuit bord.
• The type of CPU normally defines the name of a computer system. For example a core i7 system has core i7 processor as its CPU
• These days the CPUs in the most of the personal computers have more then one core. A core is an independent processing unit with int he CPU. Earlier CPUs had single core only.
• Processors those days have their own circuit borads which attach to a special slot in the motherborad.

Memory Devices

• In a computer, memory is one or more sets of chips that store data and/or program instructions, either temporarily or permanently. Memory is critical for processing in any computer. Personal computers use several different types of memory, but the two most important are called random access memory (RAM) and read-only memory. Those two types of memory work in very different ways and perform distinct functions.

Random Access Memory (RAM)

• The term memory is most commonly used for random access memory (RAM).
• RAM may be thought of as table top or an electronic scratch pad in a computer system.
• RAM hold the corrent programs/data as the CPU works with them.
• Since it is possible to read data from write data to RAM, it is also referred to as read/write memory.
• RAM stores data temporarily and is volatile as it loses its contents when the computer is turned off or in case of power failure.
• RAM significantly affects the speed of a computer. RAM enables a computer to perform tasks more quickly.
• Byte is the amount of space set aside in memory to store on such as a character or numeral.
• Storage terms such as kilobyte (KB), megabyte (MB), gigabyte (GB) and terabyte (TB) come handy to describe memory.
• Modern computers may have several gigabytes of RAM.
• Like several ther devices, RAM comprises of a number of chips contained on circuit board.

Read Only Memory (ROM)

• Read Only Memory (ROM) sores the data on a permanent basis even when the computer is powered off.
• ROM contains the boot instructions of the computer.
• When the computer is switched on, it looks up ROM for instructions that assist the computer in starting up.
• ROM also keeps the compter informed as to its hardware compnents.

Input And Output Devices

Input Devices

• Input devices allow user to interact with a computer system
• Input devices accept data from a user
  • Keyboard, mouse, trackpad (touchpad), joystick, digital camera

Output Devices

• Output Devices deliver processed data to the user
  • Monitor, Printer, Speakers

Some devices works both input and output devices ex: Touch Screen Devices.

Storage Devices

• Storage Devices holds data and programs permantely even when the computer has been powered off unlike RAM that loses its contents when the computer is shut off.
• Storage has more available space then a memory
• Storage devices are solwer as compared to RAM but they are relatively cheaper.

Typers of Storage Devices

Magnetic Storage

• Floppy drive and hard drive are best examples if Magnetic Storage
• Its used magnet to read and write data.

Optical Storage

• CD and DVD drives
• Use laser to write data to and read data from the reflective surface of a CD/DVD

Solid State Drives

• Use flash technology to store and retrive data
• Much faster than magnetic harddrives
• SSDs have significantly higher cost per byte than their magnetic counterparts

Bus Interconnection

• Every Computer consists of one or more processors, memory and input/output devices. However in order for the data to travel between these devices some from of interconnection must exist.
• Several bus interconnections exist in a computer. A bus is nothing but a set of parallel lines that allowes the data in the form of bits to travel from one component to nother.
• The main bus that connects the main components is the system bus which is further divided into data bus, address bus, and control bus.