CHAPTER 2

Computer Systems: Hardware, Software, and Connectivity

OBJECTIVES

1.Define information systems

2.Describe the major components of computer systems and their related functions

3.Define basic terminology related to hardware, software, and connectivity

4.Describe the main categories of computer software

5.Appreciate the language of information systems

INFORMATION AGE

•System:

•set of interrelated parts

•Information System:

•system that produces information using input/process/output cycle

•Basic Information System: four elements

•People

•Policies and Procedures

•Communication (connectivity), and data

TYPES OF INFORMATION SYSTEMS

•Transaction Systems

•Payroll

•Order/Entry

•Management Information Systems

•Running an organization

•Decision support systems

•Decision making

•Expert Systems

•Provide advice or make recommendations

Purpose of an Information System is to provide information to the users

•People

•The most important part of the system

•Technical Professionals

•Informatics Specialists

•Policies and procedures

•Guiding principles related to information and technology use

•Communication/Connectivity

•The electronic transfer of data from one place to another

•Introduction to Computer Systems: HARDWARE

•Input devices

•The system unit (processing unit, memory, boards, and power supply)

•Output devices

•Secondary storage devices

•Common Computer Terms

•Computer

•Bit

•Byte

•Supercomputer

•Mainframe

•Midrange

•Servers

•Microcomputer

•Mobile Devices

•Laptops

•Handheld Computers

•PDAs

•Smart Phones

•Boot

•Default

•Toggle

•Upgrade

Computer Components: Input Devices

•Hardware components

•Converts data from an external source into electronic signals understood by the computer

•Cursor or Pointer

•Visible indicator marking current location

•The point at which the work begins

Major Input Devices

•Keyboard

•Input device for typing data into the computer

•Mouse

•Input device used to access menus or functions

•Open application programs

•Create graphic elements without using function or cursor keys

Other Input Devices

•Gaming input devices

•Light guns

•Joysticks

•Dance pads

•Motion sensing controllers

•Cradles or Docking Stations

•Used with PDAs

•Laptops

•iPods

•Cameras

Other Input Devices

•Digital Camera

•Light Pen

•Microphone

•PC Video Camera

•RFID

•Scanner

•Stylus or Digital Pen

•Touch Screen

Computer Components: System Unit

•Contains the control or “brains” of the computer

•Motherboard

•The main circuit board of the system unit

•Processor

•The central unit in a computer that contains the circuitry

•The processor has two parts:

•The control unit

•The arithmetic/logic unit

Computer Components: System Unit

•Processor

•Microprocessors

•Laptop processors

•Specially Designed processors

•Chip

•A tiny piece of semiconducting material that packs millions of electronic elements

Computer Components: System Unit

•Memory

•Read-only memory (ROM)

•Memory that has been burned on the chip at the factory

•Programmable read-only memory (PROM)

•Permits instructors to be programmed on the chip only once

•Random-access memory (RAM)

•Stores data that the computer needs to use temporarily

•This memory is volatile

•Erasable programmable read-only memory (EPROM)

•Permits a user to program the instructions many times

Computer Components: System Unit

•Flash Memory

•Nonvolatile memory

•User can erase and rewrite

•Cache Memory

•Stores frequently used instructions and data

•Ports

•Highways that lead into, out of, and around the computer

•Plugs, sockets, or hot spots

Computer Components: System Unit

•Ports

•“Jack” refers to connections for audio and video ports

•Serial ports (“com” ports)

•Parallel ports (unidirectional ports)

•USB (universal serial bus)

•FireWire (special-purpose port)

Computer Components: System Unit

•SCSI: A Small Computer System Interface

•Pronounced “scuzzy”

•IrDA: an infrared light beam port connects wireless devices to the computer using light waves

•Bluetooth

•Uses radio waves to communicate between devices

•MIDI: permits connection of musical instruments to the computer

Computer Components: System Unit

•Expansion Slots

•Places on the system board where one can add cards, adapters, or other computer boards

•Power Supply

•Converts the power available at the wall socket to the power necessary to run the computer

•Registers

•Temporary, high-speed storage spaces used when processing data

Computer Components: System Unit

•Monitor

•Displays graphic images from video output

•Size: the diagonal measurement from corner to corner

•Footprint: how much space the monitor takes up on the desktop

•Color: one color or colored

•Resolution: number of horizontal and vertical pixels found on the screen

Computer Components: System Unit

•Monitors

•Response time: time it takes to turn a dot on or off

•Dot pitch: measure of the distance between the colors that make up the monitor

•Brightness: visibility light intensity of the screen

•Contrast ratio: ratio of the brightest to the darkest color on the screen

Computer Components: System Unit

•Printer

•Nonimpact printers

•Laser printers

•Thermal printers

•Ink Jet

•Plotters

•Impact printers

Other Output Devices

•Speaker and Headsets (headphones)

•Data Projectors

•Multifunction Devices

•Interactive Whiteboards

Computer Component: Secondary Storage

•Storage

•A place or space for holding data and application programs

•Secondary Storage

•Media holds application programs and user data when they are not in use

•Has a higher density and is less expensive

Storage Devices

•Hard Disks (hard drives)

•Fixed data storage devices in sealed cases

•Read stored date on platters in the drive

•Tape Drives

•Secondary storage that allow the backup or duplication of stored data on a hard disk

•Optical Drives

•An alternative to magnetic storage

•Holds large amounts of data

Storage Devices

•Solid-state media

•Flash memory cards

•USB storage devices

•Smart cards

•Labeling Disk Drives

Introduction to Computer Systems: Connectivity

•Networks

•Collection of computers and other hardware devices that are connected together

•Local area network (LAN)

•Ethernet

•Wireless local area network (WLAN)

•The metropolitan area network (MAN)

•Wide area network (WAN)

•Wireless home networks

Communication Device

•Any type of hardware capable of transmitting data and information from one computer to another

•A cable modem

•A dial-up modem

•A DSL modem

•An Ethernet card

•A Wireless card

•A wireless modem

Communications Channel

•The transmission pathway that data take to arrive at the other end of a connection

•Bandwidth

•Broadband

•Dial-up service

•Transmission media