Parts of the Computer System
Computer systems have four parts
- Mechanical devices in the computer
- Anything that can be touched
qe.g. printer, keyboard, PDA etc.
- consists of interconnected electronic devices that you can use to control the computer’s operation, input, and output.
- generic term device refers to any piece of hardware
- Set of instructions that makes the computer perform tasks
- Tell the computer what to do
- Also called a program
- Thousands of programs exist
Some for computer’s own use
Some for the service of the user
- Reason majority of the people would want to purchase a computer
E-mail, type letters, play games etc.
- Pieces of information / individual facts
- By themselves do not make much sense
- Computers organize and present data
People operating the computer
Most important part
Tell the computer what to do
- Userless computers?
- people still design, build, program, and repair computer systems.
Information Processing Cycle
- Converts data into information
The raw facts and figures that are processed into information
Data that has been summarized or otherwise manipulated for use in decision making
Steps to Process Data
Steps to Process Data
Computer accepts data from some source
Computers processing components perform actions on the data based on instructions from user or program
Computer conveys result to user.
Text, numbers, graphic, image, video, sound
Permanently store result on some medium
Essential Computer Hardware
Computers use the same basic hardware
Hardware categorized into four types
- Input and Output
The procedure that transforms raw data into useful information
To perform this transformation, the computer uses two components:
The Processor and
Brain of the Computer
A tiny piece of silicon that contains millions of miniature electronic circuits.
How does everything connect?
Main printed circuit board in the computer
Everything connects to the motherboard
Expansion slots – “plugs” on the motherboard for expanding the PC’s capabilities via additional circuit boards
- Carries out instructions from the program
- Manipulate the data
- Most computers have several processors
- Central Processing Unit (CPU)
- Secondary processors
- Processors made of silicon and copper
- memory is one or more sets of chips that store data and/or program instructions, either temporarily or permanently.
- Memory is a critical processing component in any computer
- Two most important types
Random access memory (RAM) and
Read-Only memory (ROM).
- work in very different ways and perform distinct functions
Random Access Memory
- Also known as RAM or memory
- Represent primary storage or temporary storage.
- Hold data before processing and information after processing.
- More RAM results in a faster system
- In MBs or GBs
Read Only Memory
Also called ROM
Permanent storage of programs
Holds the computer boot directions
Typically in KBs
Input hardware – devices that allow people to put data into the computer in a form that the computer can use
Allows the user to interact
Input devices accept data
Other Input Devices
- Track ball or touch pad
- Digital Camera
Output devices return processed data to the user or to another computer system.
Some devices are input and output
Coverts audio signal from digital to analog and vice versa
Both Input and Output device
the devices that play sounds transmitted as electrical signals from the sound card.
converts the processor’s output information into a video signal that can be sent through a cable to the monitor
the display device that takes the electrical signals from the video card and forms an image using points of colored light on the screen
a device that sends and receives data over telephone lines to and from computers..
Network Interface Cards (NIC)
Controls the flow of data on a network link
Hold data and programs permanently
Electronic file cabinet
Difference between storage and memory
- More capacity in storage
- Contents are retained in storage even the power is off
- Storage is much cheaper
- Access speed is slow
Types of Storage Devices