This document provides an overview of hardware and systems technology, covering topics like computers, input/output devices, data storage, communication devices, networks, and more. It defines key computer components and terms, describes common data types and file formats, explains how data is processed and transmitted, and outlines computer system organization from the CPU up through local and wide area networks. The document is intended to cover 15% of the content on an upcoming exam.

1. Hardware and Systems
Technology
This section will make up 15% of the questions on the exam.

2. Computers
 Computer – an electronic device (made up of hardware and
software) that is programmable to perform specific functions or
tasks.
 Computer hardware – the physical components of a computer
 Software – programs that allow a computer to carry out its
function.
 IPOS cycle – used by computers to perform a task. (Input,
Processing, Output, Storage)
 Data – information that has not yet been processed (text,
numerical, audio, image, video etc.)
 Information – data that has been processed

3. Cont.
 Input devices – mouse/keyboard
 Output devices – monitor
 Processing devices - CPU
 Storage devices – hard disks
 Storage media – flash memory cards
 Communication devices – modem
 Operating system – is required to manage a computers soft
and hardware. It also allows the computer to run programs.

4. Cont.
IPOS Cycle
1. Input – data is entered into the computer
2. Processing – data is transformed to information
3. Output – information is presented as results of an operation
4. Storage – saves the information for future use
 Basic Data types – text (string) data (letters, numbers and special
characters), graphic data( photos and drawings), audio
data(sounds), video data(moving pictures and images), time/date
(the day and time of a specific event) and multimedia data
(combination of text, number, audio and video)

5. Cont.
 Any piece of data typed into a computer is converted into a binary number system.
 Base of a number system – how many digits will be used in expressing a number.
 In order to find the total value that is stored in a system you ad the value of every number raised to its base. Any thing that
is typed into a computer is transformed into its decimal equivalent and then a binary code.
 Computers understand machine language which uses only 0’s and 1’s. (0 represents an OFF state and 1 indicates
represents an ON state)
 0’s and 1’s represent bits (the smallest unit of information)
 A byte represents a group of eight bits
 Digital data – data that is in its binary digit form (machine language)
 American Stand Code for Information Interchange (ASCII) and the Extended Binary-Code Decimal Interchange Code
(EBCDIC) systems use binary 8 digit patterns (consisting of 0’s and 1’s).
 This system represents 256 characters (digits 0-9, lower/upper case English letters, special characters and control
information)

6. Cont.
 Unicode system – a universal coding standard that
represents the ASCII and EBCDIC code in addition to other
languages.
 Operator – special symbols that are used to perform
operations.
 Operands – numerical values of which the operation is
performed.
 Assignment operator – assigns the calculated result.
 Ex. D= 3-1 (D is the difference of 3 and 1) (3 and 1 are the
operands) (= is the assignment operator)

7. Cont.
 Supercomputers – used to perform complex mathematical equations.
 Mainframe computers – used by large companies to allow thousands of people to perform a task at the same time.
 Personal computers – compact computers.
 Mobile devices- portable and mobile computers.
 Cell phones – a mobile computing device used to call others (they have their own operating systems).
 Personal digital assistants (PDA) – hand held devices.
 Global positioning systems (GPS) – a collection of satellites that were designed and built by the military.
 Portable media players (PMP) – play audio or video
 Laptop – portable computers that are equal in power to personal computers
 Embedded computers – chips put inside of another devices

8. Hard/Software
Types of hardware
1. Input devices
2. Processing devices
3. Output devices
4. Storage devices
5. Communication devices
6. Network devices
 I-pen – used as a pen or mouse.
 Digital peg – computes
handwriting into a readable form
on a computer.
 POS devices – used by retailers.
 Biometric input devices – use the
body for recognition (ex.
Eye/finger print).
 ATM – used at banks.
 Scanning devices – magnetic card
readers, bar codes, RFID tags
and fax machines.

9. Cont.
 Motherboard – the main part of a CSU.
 RAM – temporary memory that is erased when the computer is
turned off.
 Large RAM + fast CPU = fast computer
 Ram is measured in MB, CPU’s are measured in Gigahertz.
 Chipset – is used to connect the CPU to other parts of the
computer system
 CPU – the “brain” of the computer (a chip mounted on the
motherboard)
 Expansion slots – are located on the back of a system unit to add
other functions/components.

10. Cont.
Memory Hierarchy
1. CPU registers – stores items that are ready
to be processed or that are being
processed
2. Cache level 1 - stores most the CPU’s most
frequently used items
3. Cache level 2 - stores most the CPU’s
frequently used items
4. Cache level 3 - stores most the CPU’s least
frequently used items
5. RAM (random access memory) – stores
the operating system and other files used
when the computer is on
6. Secondary storage devices (hard disk) –
stores files when the computer is off
Types of ports
 Serial ports – send one bit of data at a time
 Parallel ports – send multiple bits of data at a time
 Universal serial bus (USB)
 Connectivity ports – allow computers to communicate
with other computers
 Ethernet ports
 Fire wire ports – allow for faster transferring of data
 Graphic ports
 Audio ports
 Speaker ports

11. Cont.
Components of a CPU
 Arithmetic/Logic Unit (ALU) – performs al logical and arithmetical tasks
 Control Unit – manages all of the computers operations
 CPU Registers – a special storage area only usable by the CPU
The CPU Machine Cycle
1. Fetch instructions
2. Decode instructions
3. Execute instructions
4. Store results in the CPU registers
 Computer output devices – present information in human language types of information include (text,
numerical, audio, graphics pictures alphanumeric and video)

12. Cont.
 Computer monitors – a soft-copy output device (CRT – old
version) (LCD – new version).
 Pixel – a single point on any image.
 Resolution – the number of pixels horizontally and vertically.
 Dot pitch- the distance between the center of two pixels.
 Printers are measured in PPM (pages per minute).
 On impact printers – use wire pins that touch the paper.
 Non-impact printers – the paper is not touched.

13. Cont.
 Photo printer – print high quality
 Laser Print – print high-quality and high speed (non-impact)
 Large format printers – print pages >60 inches in width
 Fax Machines – use telephone lines to send or receive documents
 All computers contain a small audio device
 Magnetic storage devices use magnetics to store information. 0’s represent a non magnetized particle
and 1’s represent a magnetized particle. When being read the reader picks up the magnetized
particles.
 Without formatting a hard disk no information can be stored on it.
 File allocation table – contains a directory of the topics on the disk.
 Root directory – puts the data into different folders.
 Units of memory from smallest to large (byte, kilobyte, megabyte, gigabyte, terabyte, petabyte)

14. Storage Devices
 Tracks – concentric circles that a hard disk is divided
into during formatting.
 Sector – a subdivision of each track.
 Cluster – a group of sectors (2-8)
 Platters – are made from a rigid material and consist of
tracks and sectors.
 USB drives – non-volatile storage devices that are
portable.

15. Cont.
 Both CD’s and DVD’s are made from plastic
 CD-ROM – can be written on once (used for computer software)
 DVD-ROM – can be written on once
 CD-R - can be recorded on once
 DVD-R, DVD+R – can be recorded on once
 CD-RW, DVD-RW – can be recorded on several times
 DVD-RAM- can be recorded on several times
 DVD-Video – used to record movies
 DVD-Audio – used to store music
 Blu-ray was designed to replace DVD

16. Cont.
 In order to read from a disk a beam is shined onto it and the pits (area with information)
will absorb the light. The computer will then read this area as a 1.
 A communication medium is needed to transfer data.
 Transmission = communication
 Fiber optic cables – use light pulses to send information through a fiber or plastic wire.
 Twisted-pair cables – consist of two twisted copper wires that are wrapped in an
insulation.
 Coaxial cables – are made by two parallel copper wires that can each carry a signal.
 Digital subscriber line (DSL) – uses telephone network cables to transmit internet. This
allows for surfing the web, while talking on the telephone (not available everywhere).

17. Communication
 Wireless communication – uses either radio waves or infrared light.
 Wi-Fi – Wireless Fidelity, follows IEEE standards.
 Wireless access points (WAP) – provide the internet connection to various
devices.
 Integrated Services Digital Network (ISDN) – works the same way as DSL, but
is more expensive.
 Communication satellites – receive waves from earth and amplify them back
at the earth.
 Microwave technology – requires line of sight.
 Cellular technology – allows people to communicate without cables (virtually
from anywhere)

18. Cont.
 Packets are involved in packet-switched networks. One packet can
carry one unit of binary data.
 A typical packet is between 1,000-1,500 bytes.
 Packet header – contains the IP address for the message’s
destination.
 Packet Body – the message being sent.
 Packet footer – the end of the message.
 Packet destination – receives and reassembles the message.
 Packet switching – subdivides a message to transmit it to its
destination.

19. Cont.
 Modem – involves both modulating and demodulating by converting analog signals to
digital signals and vise versa.
 Internal modems- are inside computers.
 Wireless modems – found in mobile devices.
 Dial-up models- convert a digital signal to an analog signal.
 Cable modems – use a cable television network to communicate.
 ISDN modems – use ISDN data as a communication medium.
 DSL modems – use DSL data as a communication medium.
 Communication path via modems (Computer A, Modem A, Communication medium,
Modem B, Computer B)
 Network interference card – allows a computer to communicate with other computers via
a network.

20. Cont.
 Computer network devices – mediate data in a computer
network (ex. Switches or gateways).
 Node – a point at which two networks intersect.
 Network node – anything that can send information via a
medium.
 OSI Model – each layer provides services to the layer above
it and receives service from the layer below it.
 Layers from top to bottom – Application layer, presentation
layer, session layer, transport layer, network layer, data-link
layer, physical layer.

21. Cont.
 Gateway – interfaces between two networks that use different protocols (each network has its own
protocols).
 Switch- handles and controls data communication.
 Bridge- transfers data between two LANs.
 Hub- connects all computers in a LAN.
 Repeater –amplifies the strength of an incoming signal.
 Network router – links multiple networks.
 Each computer system is made up of 3 components
1. System unit – the plastic/metal frame that stores everything.
2. Monitor- projects the information in human language.
3. Keyboard/mouse – input devices.

22. Cont.
 Computer network – allows for communication between devices.
 Communication protocols – standard rules that control how data will be communicated between
computers in a network (ex. HTTP, FTP, TCP/IP)
 Local area network (LAN) – computers are close in proximity. Has one computer that is a server
computer that will allow for easy access by other computers.
 Wide area network (WAN) – computers are not close in proximity.
 Metropolitan area network (MAN) – a type of WAN that covers a city.
 Value added network (VAN) – is a type of WAN that allows a company to provide network connections
between multiple parties.
 Enterprise Network Architecture – the use of multiple devices to allow an organization or departments
to share and access information more easily.
 Web browsers – are universal.
 Web servers – provide data to web browsers.