CS 3 - Kurtz  Santa Monica College 




Ink-jet Printers 


Spray magnetized ink onto paper
Ink cartridges are replaced when they run dry
Cartridges for black, yellow, magenta, and cyan
Color cartridges are often combined into one.
Cost is low enough for home use
Popular for inexpensive color printing


Dot Matrix Printers 


Tiny solenoids "impact" an inked ribbon against paper
The ribbon is replaced when it gets dry.
Inexpensive, rugged, and noisy
Used on multi-part forms
Low print quality


Laser Printers 


Laser writes to a light sensitive drum which transfers toner to paper
A toner cartridge is replaced when toner is expended.
Toner cartridge also contains the print drum.
Robust enough for shared office use


Thermal Printers 


Paper reacts to heat and electrical charge and changes color
Special coated paper is required
Very inexpensive
Low print quality
Images tend to fade over time


Cathode Ray Tube 


 Type of video monitor 
Similar to a television screen 
Beam of electrons is emitted by an electron gun (cathode) which illuminates phosphors on the screen, causing them to glow 
Monochrome monitors use one electron gun 
Color monitors require three electron guns, red, green, and blue (RGB) 
Monitor screens are made up of individual pixels or picture elements 
More pixels make images smaller and smoother
Typical PC Monitor resolutions: 

800 x 600 (800 pixels across and 600 pixels down) 
1024 x 768
1280 x 1024


Liquid Crystal Device

Uses Liquid Crystal Material sandwiched between polymer layers
LCD elements are activated by an electrical current.
Active matrix, or TFT technology is brighter, has better color, is visible at an angle, but more power is required than passive matrix LCD devices.
Passive matrix requires less power than TFT, but is visible only from front.
Generally have low power requirements and are suitable for mobile (battery) use
Take up less space than CRT monitors


Alphanumeric Keys 


Letters, numbers, and punctuation marks
"QWERTY" arrangement similar to typewriter


Function Keys 


Labeled F1, F2, etc. 
Get their meaning from the program being executed
Have no intrinsic function


Cursor Keys 


Used to move cursor on screen 
Arrow keys, PgUp, PgDn, Home, End


Numeric Keypad 


Similar to a 10-key calculator keypad


Special Keys 


NumLock, Control, Shift, Alt, Esc, Insert, Del, Enter, Backspace


Capture an image of a document directly
Resolution in dots per inch (dps)

Optical Character Recognition

Used to convert scanned document images into a native format such as Word, Excel, etc.

Optical Mark Recognition

Scans for marks on a form such as a Scan-tron

Magnetic Ink Character Recognition

Recognizes Magnetic Ink in shape of special characters
Used primarily in banking industry

Bar Codes

Optically scanned
Used in retail (grocery, pharmacy, hardware, stationary, etc.),
Vehicles, mail, books, etc.

Plotters and Large Format Printers

Used in engineering, drafting, and graphic arts
Large Format Printer
Electrostatic Plotter
Pen Plotter
Used for large printed output

Audio Output

Speakers & Headsets


Can be a good output device
Analog televisions usually require a converter
Digital Television (DTV) is generally superior to analog television
High Definition Television (HDTV) is an advanced form of DTV