BPC 101AA

INTRODUCTION TO COMPUTERS 1

The Pearson Custom Program for CIS, BPC101AA, Introduction to Computers I, Phoenix College; Copyright 2011 by Pearson Learning Solutions

IDENTIFYING COMPUTER COMPONENTS and THEIR FUNCTIONS

CHAPTER 2

LESSON ONE:

IDENTIFYING BASIC INPUT and OUTPUT COMPONENTS

MONITORS:

Cathode Ray Tube (CRT) On older computers Uses a glass picture tube, similar to picture tubes in older

televisions Liquid Crystal Display (LCD)

Uses a fluorescent light behind a flat panel Electrical charges make picture elements, or pixels The number of pixels per inch displayed on the screen

determines the resolution, or level of detail More pixels per inch = higher resolution

THE MOUSE:

A device that controls a pointer on the screen Mouse with a rubber ball

The rubber ball presses against 2 rollers that are perpendicular to each other

This action allows the pointer to move according to left-to-right position and the up-and-down position

Optical mouse Uses reflected beams of light instead of rollers

Thumb mouse The user moves a track ball directly to control the pointer

See Table 2 on page 51 for mouse instructions Practice using the mouse on pages 52 - 53

Mouse Alternatives for Notebook Computers

Pointing stick A small knob that responds to sideways pressure

Touch pad A small, rectangular, flat area that senses the

position of your finger when you touch it

KEYBOARD:

Each keystroke is converted to a binary number that the computer understands

Function keys at the top can be programmed to perform special functions

Control Key, Alternate Key, Shift Key Used in combination with other keys for special commands

Num Lock Key A key that toggles the numeric keys’ function between the

navigation arrows and numbers Control, Alt, Delete Keys

Brings up a dialog box that enables you to close the program if it is not responding

OPTICAL DISCS:

Disks – Media used to store information using magnetic methods

Discs – Media used to store information using optical methods

Compact disc (CD) – Media used to store information as binary numbers (burning a pit for 0 and an unmarked surface, land, for 1)

Read-only drives – reads data on a disc, but can’t alter or write data on a blank disc

Writable drives – can write to writable discs

TYPES OF OPTICAL DISCS:

CD (compact disc) CD-ROM: read-only memory CD-R: blank disc that can be recorded on CD-RW: can be written to and erased many times

DVD (digital video disc) DVD-ROM: read-only that can be on 2 different layers and on both sides of the disc DVD-R: can be written on once DVD-RW: can be written on and erased many times

BLU-RAY – ability to store 25 gigabytes on a single-layer disc and 50 gigabytes on a double-layer disc

BD-ROM: read-only BD-R: write once BD-RE: erased and recorded many times

FLASH MEMORY

A type of memory that is not as fast as RAM, but does not require constant power

Compact flash cards – used in expensive cameras Secure Digital (SD) cards & MicroSD cards – used in

cameras, cell phones, smartphones, PDA’s Flash drives, Thumb drives, USB drives – transports files

from computer to computer and plugs into a USB port Flash hard drives – used in notebook computers and don’t

use as much energy as magnetic hard drives

EXTERNAL HARD DRIVE:

All computers come with an internal hard drive, which is the main storage unit in the computer

External hard drives are additional storage when the internal drive is full and to backup important data files.

PRINTERS:

Impact printer – typewriter technology in which a metal rod struck an ink-fused ribbon, and the impact transferred the ink to the paper to make a dot.

Dot matrix printer – produces patterns of dots that form text characters. Laser printer – transferring powdered ink to paper, then heating the ink

to make it stick to the paper. Toner – powdered ink that is melted into the paper

Ink-jet printer – liquid ink that is directed to the paper using electric fields. Four colors (black, magenta, cyan, yellow) combine to produce all the other colors.

SPEAKERS:

Speakers are used to play music, videos, sound effects, speaking content of documents

External speakers Monitors with built-in speakers Subwoofer – a large speaker to play low bass notes Speakers inside the computer’s system unit

To alert the user of a hardware problem

MICROPHONES:

Microphones pick up sounds and convert them to analog signals

The computer uses A to D converter to change the sounds into binary numbers

Voice recognition – computer programs that translate what you say into text for a document or e-mail

LESSON TWO:

IDENTIFYING SPECIALIZED INPUT DEVICES

GAME CONTROLLERS:

Gamepad – a specialized input device to control the action in a computerized game

Joystick – a game controller that uses a rotating ball inside the case

Nintendo Wii – a wireless controller that enables you to play golf, tennis, the guitar, etc.

DIGITAL CAMERAS:STILL and VIDEO

Uses light-sensitive detectors that convert the image into electrical signals and fed into an A to D converter

Megapixels (millions of pixels) – the higher number of megapixels means better resolution and larger picture sizes when the image is printed 1,280 x 960 = 1.2-megapixel image 4,000 x 3,000 = 12-megapixel image

DIGITAL CAMERAS:STILL and VIDEO

Docking station – a place where the camera sits to transfer images to the computer

Flash memory or SD cards – removed from the camera and placed in a card reader that is connected by a wire to the computer to transfer images

DIGITAL CAMERAS:STILL and VIDEO

Point-and-shoot camera – smallest and least expensive with automatic focus and shutter speeds

Digital single lens reflex (DSLR) camera – more expensive and larger. The photographer controls the settings.

DIGITAL CAMERAS:STILL and VIDEO

Frames per second – the number of pictures taken by a digital video camera in one second. It takes 30 frames per second to simulate smooth motion It takes 15 frames per second for transmission over the

Internet

Web cams – video cameras that are attached to a computer for videoconferencing or monitoring

SCANNERS:

Scanners convert an image into digital data so a picture can be input into a computer

Flatbed scanner – a document is placed on a pane of glass and a fluorescent lamp travels the length of the document. The reflected light converts to numbers using an A to D converter

Document scanner – uses a stationary lamp and the paper moves past the lamp. Used when many sheets of paper need to be scanned.

Optical character recognition (OCR) program – a computer program that recognizes the image and converts it to ASCII or Unicode number.

GRAPHICS TABLETS:

Used by architects, mechanical engineers, photographers, and animation artists to create drawings and process photographs

BAR CODE READER:

A narrow beam of light and sensor that converts the flickering reflection into binary numbers the computer can read.

They are used in conjunction with a database for pricing and inventory control for objects such as groceries, clothes, music CDs, etc.

RADIO FREQUENCY ID (RFID)

A device that uses radio frequencies to remotely retrieve data

An example is in cars on toll highways. An RFID device is attached to the windshield and the signal is read to deduct the toll amount from the driver’s account.

TOUCH SCREEN:

Monitors that act as input devices Used in some stores to allow customers to check

out

Stylus – a penlike device that is used to tap the screen

SENSORS and PROBES:

Sensor – detects the status of something and responds to changes in a predictable manner by producing an electric signal Alarm systems

Probes – sensors that explore hard to access places Oxygen sensor in the exhaust pipe of a car,

probes that sense the movement of the earth

REMOTE CONTROLS:

Wireless devices used for appliances such as music CD players, TVs, etc.

Infrared light – an invisible light that transmits the binary number to the appliance. The remote must be pointed to the infrared sensor on the appliance.

Radio waves – waves that transmit the binary number to the appliance. The waves spread out in all directions and do not have to be pointed at the appliance.

SECURITY DEVICES:

Passwords Swipe cards Biometric device – matches a user’s

biological information such as fingerprint or retinal scan with patterns stored in a database to identify authorized users.

SPECIALIZED INPUT DEVICES:

Adaptive computer devices – for use by people with special needs Miniature keyboards Keyboards with tactile surfaces One-handed keyboards