- Four Types of Input
- Software transfers from storage to memory, data, commands, and
- An arrangement of letter, number, and special function keys that
acts as the primary input device to a computer.
- The keyboard function of entering multiple copies of of a character
when a key is held down.
- Dialog Box.
- An on-screen window that provides options associated with a command.
A type of window that provides for input of information needed by
- Enhanced Keyboard.
- The typical PC keyboard with 101 key. The equivalent Macintosh
keyboard is called the extended keyboard.
- Cordless Keyboard.
- Battery-powered keyboards that send signals with infrared or radio
waves, also called "wireless keyboards."
- Cursor-Movement Keys.
- Keys used to move the cursor (insertion point) in a document, including
the arrow, the end, home, page up, and page down keys.
- Numeric Keypad.
- A calculator-style input device for entering numbers and arithmetic
symbols, part of the extended computer keyboard used enter numerical
- Toggle Key.
- A key, such as the "caps lock" or "num lock"
keys, that switches a device back and forth between two modes.
- Function Keys.
- The keys numbered Fl through F12, located at the top of the computer
keyboard, that activate program-specific commands. F1 is often used
- Escape Key.
- A key labeled "esc" with program specific functions,
generally used to interrupt or cancel an operation.
- Modifier Keys.
- Keys that, while they are held down, modify the meaning and input
of other pressed key. The "alt" and "ctrl" keys
on PCs and the control and command (apple) keys on Macintosh computers.
- Diacritical Marks.
- Marks added to letters or symbols to distinguish it in some way,
often indicating pronunciation.
- Dead Key.
- A type of keyboard shortcut used to modify the following character,
such as adding diacritical marks.
- A palm-sized input device that allows the user to manipulate objects
on the screen by mirroring movements on a surface.
- Pointing Device.
- The device, typically a mouse or touchpad, that provides control
of the on-screen pointer.
- A pointing device consisting of a ball that is rotated to move
the pointer on the computer screen.
- A pressure-sensitive input device used to control the on-screen
pointer by moving the fingertips over the pad's surface.
- An input device with a vertical lever moved to control pointing
devices or on-screen objects.
- Sound Card.
- A circuit board that gives a computer the ability to accept audio
input and produce audio output.
- Data Compression.
- The process of making a data file more compact. Image compression
typically removes repetition or utilizes averaging. Text documents
are compressed using abbreviations.
- A highly compressed file format for digital video and audio files.
MPEG is short for "Moving Pictures Expert Group."
- Short for picture element, a pixel is the smallest unit in a graphic
image. Computer display devices use a matrix of pixels to display
text and graphics, typically 72 pixels or dots per inch (dpi).
- Charge-Coupled Device.
- A photosensitive computer chip that transforms light patterns into
- The process of transferring a copy of a file from a remote computer
to a computer's drive.
- Video Capture Card.
- Computer circuitry that transforms analog video into a digital
video file, typically using on-the-fly data compression.
- A charge-coupled device for digitizing images.
- The density of the grid used to display or print text and graphics.
The greater the horizontal and vertical density, the higher the resolution.
- Bit Depth.
- The number of bits used to represent a pixel.
- Optical Character Recognition (OCR).
- The process of converting images of text into digital text files.
- Facsimile Machine (FAX).
- A device that transmits scanned images of documents via telephone
- Frame Rate.
- In video output, the number of still images displayed per second.
- Graphics Card.
- A computer circuit board to handle the display of text, graphics,
animation, and videos. Also called a video card, video adapter, or
display adapter. The video adapter determines the display quality.
- Video Memory (VRAM).
- Memory located on a graphics card that store images as they are
processed, accelerating processing by freeing RAM and the CPU to perform
- Video Graphics Adapter (VGA) Standard.
- The 640 x 480 color graphic display standard. Super VGA is the
1024 x 768 standard.
- Color Depth.
- The number of colors that can be displayed at one time. Bit depth
determines the range of possible colors. For example, an 8-bit color
depth can create 256 colors, and a 24-bit depth displays 16.7 million
- Refresh Rate.
- The update frequency rate of a display, measured in cycles per
- An output device that displays an image by converting electrical
signals into points of light.
- Cathode Ray Tube (CRT).
- A display technology using a vacuum tube, similar to a television
set. CRT technology used an electron stream and a phosphorescent screen.
- Liquid Crystal Display (LCD).
- Flat panel computer display in which light passes through a thin
layer of liquid crystal cells to produce an image.
- Dot Pitch.
- A measure of image clarity, the diagonal distance between dots
on a display, measured in millimeters.
- Multiscan Monitor.
- A monitor designed to adjust its refresh rate to the video adapter
- Ink Jet Printer.
- A non-impact printer that creates imagery composed of tiny dots
by spraying liquid ink.
- Laser Printer.
- A printer that uses laser-based technology, creating electrical
charges on a rotating drum to attract toner. The toner is fused to
paper using a heat process.
- Musical Instrument Digital Interface (MIDI).
- Text file standards to encode and transmit sound and music. FM
synthesis is the older standard, and wavetable is the newer, higher-quality