Computer Concepts  
What's a

A Programmable electronic device that can store, retrieve, and process data.

Types of


Ex: IBM's Blue Gene/P (over $1.5 million per rack)


  • Requires special staff and environment
  • Fastest, largest, costliest
  • Multi-user : 10,000
  • Used for research (Argonne National Lab), weather forecasting, aircraft design, simulation, special effects


Mainframe Computers

Ex: IBM System z10 mainframe ($100,000 and up)

  • Requires special staff and environment
  • Fast, large capacity
  • Multi-user : thousands of users
  • Used by large organizations - banks, univ, insurance co.



Ex: Dell PC ($400 and up)
Intel Pentium dual-core processor E5200 (2MB, 2.5GHz)



Ex: Apple: 13-inch MacBook ($1,000 - $1,700)


  • Single-user (typically) or Multi-user : 1 - 100 or more
  • Small, portable, desktop machine
  • High-end (workstation) Used by engineers and scientists for CAD, high vol. number crunching
  • Used by individuals for personal use or in business networked
Smaller size -

processors (vacuum tubes -> transistors ->IC chip)


Microprocessor - miniaturized circuitry that processes the data, etched onto a sliver (chip) of silicon (found in sand).


More powerful - miniaturization allows computer to house more components, processing over shorter "distances".

Less expensive - miniaturization allows computers to be used more places and for more purposes - mass production decreases price / assembly line used for smaller components.

hardware HARDWARE 

Physical components of a computer.

Input Hardware

Devices that allow data to be put into the computer.

  • Keyboard
  • Mouse, trackball, joystick
  • Digital Camera
  • Scanning device

Output Hardware

Devices that translate processed data into a form that humans can understand.

  • Speakers (beeps, tones, music, speech)
  • Screen (monitor, CRT, flat-panel display) - softcopy
  • Printer, plotter (dot-matrix, laser, ink-jet) - hardcopy

Processor &
Processing Hardware

The component that is the brains of the computer.

     Central Processing Unit ... multi-core technology
     controls and manipulates the data.

Memory Hardware

The components that store operational data & information

    Random Access Memory
    primary storage, main memory

Components that store the programs and data that are actively being used.


  • Electricity represents data & info
  • Volatile - Changes when status of electricity changes
  • Random Access to data & info
  • Memory size determines the size of programs & data


    Read Only Memory (not volatile, not erasable)
    Component that stores hardwired instructions to
    controls basic operations
    "Boots up the computer"

Secondary Storage Hardware

Devices that store data & programs permanently


  • Drive - Device that reads & write data on medium.
  • Backup - Duplicate copy of data stored on secondary storage.

Examples of media:

  • magnetic floppy disk(1.44 MB)
  • magnetic hard disk(30GB -??)
  • magnetic tape
  • CD (700 MB), CD-R, CD-RW
  • ZIP (100 MB, 250 MB, 750 MB),
  • DVD (17 GB), DVD-R, DVD-RW
  • USB jump drive (20MB - ??) (thumb drive)
Memory &
Secondary storage
Data - Organized into the following units
  • Bits - Binary digIT (electrical states)
  • Byte - Character - group of 8 bits that represents a letter, number, or special symbol.
  • Nibble - 4 bits
  • Word -group of bits processed simultaneously (16 to 128 bits)

Units of measure for data -

byte - 1 character
kilo - thousand kilobyte (K) - 1024 characters
mega - million megabyte (MB) - over 1 million characters
giga - billion gigabyte (GB) - over 1 billion characters
tera - trillion terabyte (TB) - 1 trillion characters

Communication Hardware

Devices that allow a computer to communicate with geographically separate devices.

Modem - Modulator/Demodulator - Electronic device that allows a computer to communicate over the telephone lines.

DSL Modem - Allows your computer to connect to the phone line using the high-speed DSL connection.

Cable Modem - Allows your computer to connect to the cable connection.

Network card - wired or wireless card to connect to a LAN.


Router - Device to route two or more computers communication.

Ethernet cable - cable to connect computer to router or cable modem.


software SOFTWARE

(Programs) The executable step by step instructions that tell the computer how to perform a process or task.



System Software

(operating system) Software that enables the user and application software to interact with the computer. Helps manage computer resources.

  • Windows Vista, XP, NT, 98, 2000
  • Mac OSX
  • DOS
  • Linux
  • VMS
Application Software

Software that can perform useful work on general-purpose tasks.

  • word processing software (MS Word 2007)
  • spreadsheet software (MS Excel 2007)
  • presentation software (MS PowerPoint 2007)
  • website development software (MS FrontPage 2003)
  • game software (Doom 3)
  • educational software (Yukon Trail, Kid Pix)