3 Basic Components of Computer System Hardware - it refers to the tangible components of a computer system.3 Groups of Hardware Components: 1. Input Device/s perform the two most basic computing tasks such as Issuing command and Data Entry.

Esc/Escape key is usually located in the upper-left corner of the keyboard. Function keys used to perform specific commands/instructions for a specific program. Enter/Return key used to move down one line. Cursor key used for moving up, down, left or right. Spacebar is a longest key used for generating spaces. Other keys; Alt/Alternate, Ctrl/Control, Isrt/Insert, Del/Delete, Home, End, PgUp/PageUp,PgDn/PageDown, Print Screen SysRq, ScrollLock, Pause Break, Wake up, Sleep, Power. Keyboard is the standard input device of most computers. It was patterned after the typewriter and standard calculator. Several other keys added such as;

Mouse is hand-clicked devise used for pointing. Built by Douglas Engelbart in 1963. Types of Mice:1. Mechanical Mouse has a rubber or metal ball on its undersidethat rool in all directions.2. Optomechanical Mouse same as a mechanical mouse, but usesoptical sensors to detect motion of the ball.

3. Optical Mouse uses a laser to detect the mouse's movement.

Trackball is like a stationary, upside down mouse. Joystick is an input device, which is commonly used for computer games.

Light Pen is a device used to draw, write, or issue commands when it touches a specially designed screen. Video Digitizer use images from digital camera, video cameras, camcorders, VCRs, and Optical Disk players as input to computers.

Scanner is a light-sensitive device to enter text and even graphics. Ex. OCR/Optical Character Recognition, early models of the scanner used to work with text printed in OCR format.2 Categories of Scanners:1. Flatbed scanner is ideal for materials printed in a flat surface.2. Hand-held scanner is used to capture images in materials which are not flat. Readers are used as input devices for both text and Braille

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b. Output Device/s are classified into two: Hardcopy is an output which you can hold in your hands. Softcopy is an output that can be easily modified by the computer.

Printer provides hard copy output on paper.2 Categories of Printer: 1. Impact printer produces an output by using a mechanism that presses against an inked ribbon on paper. Ex. Dot-matrix printer, Letter-quality printer2. Non-impact printer uses a photocopier-like process to transfer ink to a piece of paper. Ex. Laser printer

Plotter is a specialized kind of a printer which is used for producing large and complex scientific and engineering hard copies such as plans and maps.

Video Monitor/Display is used to provide soft copy output.2 Categories of Video Monitors: 1. Monochrome display is a single color displayed against a different colored background, such as green on green, amber on black, or white on black.2. Colored display can show a variety of colors.

Speakers are used for audio output such as beeps, human voice and music. Input/Output Devices/ I/O Devices; MODEM (Modulation, Demodulation) it translates analog signal to digital signals into something which can be understood bycomputer and vice-versa.

Other I/O device

Headset

PC Camera

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AssignmentWhat is a System Unit?What are 3 components of Microprocessor /CPU?What are the 2 types of Secondary Storage? Give at least 2 examples in each type of secondary storage.