ontap - computer hardware 1
TRANSCRIPT
ICT SHSM Certification Test – Part 1
Hardware vs. Software
Hardware refers to the physical parts of the computer – things you can see and touch.
Eg. monitor, keyboard, CPU, RAM
Software refers to the sets of instructions written by programmers so that the computer can perform certain tasks.
Eg. word processor, web browser, spreadsheet program
Bits and Bytes Information is stored within a computer
as a series of 0s and 1s This system of using 0s and 1s is called
the BINARY number system Each 0 or 1 is called a BIT (short for
“binary digit”) Each 0 represents an off “switch” or a
low voltage flowing through a circuit Each 1 represents an on “switch” or a
high voltage flowing through a circuit
Bits and Bytes Bits are arranged in groups of eight Each group of eight bits is called a BYTE Eg. 10110110 is an example of a byte Within a computer, bits and bytes are used
to represent all types of data: letters, numbers, colours, sound, etc.
When hardware components communicate with each other, they send 0s and 1s using voltages across a wire, light pulses, or wireless technology
Simple Model of a Computer Computer hardware can be organized into 7
general categories:Processing – the “brain” of the computer
Input – devices which take data from the user to the CPU
Output – devices which take data from the CPU back to the user
Primary Storage – short-term memory
Secondary Storage – long-term memory
Architecture – connects all the other parts together
Networking – allows computers to talk to each other, either locally or over the Internet
Input Processing Output
Primary
Storage
Secondary
StorageNetworking
Architecture
Simple Model of a Computer
Processing
Each computer contains one or more CPUs, which act as the “brain” of the computer
CPU = Central Processing Unit The CPU is essentially a large computer
chip which plugs into the motherboard The CPU contains millions of electronic
components called transistors, which act like switches
Processing
ControlUnit
Arithmetic-LogicUnit
Storage
There are 3 areas within a CPU:
Processing
ALU – Arithmetic Logic UnitThis part of the CPU does the mathematical
calculations and logical comparisons Control Unit
Directs traffic within the CPU and decides which instructions are to be executed at which time
StorageStores input data, intermediate processing
results, and data waiting to be outputted
Processing
CPUs are compared according to their clock rates, measured in Hertz (Hz).
Current computers contain 2, 4 or more processors within a CPU (dual-core, quad-core, …)
Because processors generate heat, cooling systems including fans and heat sinks are required to prevent over-heating.
Processing
The pins on the underside of a CPU “chip”, which plug into a computer’s motherboard.
A CPU chip plugged into a motherboard. A fan and/or heat sink will be attached to the top to prevent over-heating.
Input Devices
An input device is a piece of computer hardware that takes data from the user to the processor.
Examples of input devices include: mouse, keyboard, microphone, scanner, touch screen, joystick, game controller.
Input Devices
Mouse
Keyboard
Graphics Tablet
Joystick
Microphone
Scanner
Output Devices
An output device is a piece of computer hardware that takes data from the processor back to the user.
Examples of output devices include: monitor, printer, speakers.
Output Devices
Speakers
Monitor
Printer