Year 9 Theory

GCSE Unit One: Systems and Applications inIT.

Current and Emerging Technologies.

Hardware= the parts ofthe computer that you can simply touch e.g. the monitor, the processor

Software= the programsthat we install into the hardware. Software is a set of instructions that tellthe computer how to operate.

Computer System.

Amotherboard= this connects all of the devices together. Itis where you plug in all of your equipment.

A CPU=Central Processing unit. This is where all of the computersoperations are carried out.

Asound card= this controls the sound output from thecomputer

Internal memory= thisis used for storing the start up instructions and stores the software which youare using.

Using Computer Systems.

When you are using a computer system you can:

1. Turn it on

2. Log on

3. Refresh

4. Log Off

5. Shut Down –turns offthe computer safely.

6. Stand By –Power SaveMode

7. Hibernate- Also a powersave mode but saves the work you have done.

8. Restart-restarts thememory when your computer crashes, freezes or has completed an update.

Common Problems.

Name and describe the problems, what do youdo to prevent them?

1. Freezing and

Prevent By: Hardware drivers should be updated on a regular basisor do a disk clean up or Ctrl + Alt + Delete or restart the computer.

2. Clicking sounds, Vibrations

Prevent By: whirling or whining might come from damaged electroniccomponents. Remove the computer case and let the computer run to see if you canfind the problem.

3.Blue-Screens And Un-Planned Auto Boot.

Prevent By: Hardware issues can also cause computer problems.Attribute these problems to fading power supplies or defective parts, includingcooling fans. Keep the fan cleaned and make sure all cables and plugs aretightly connected.

4.Crashing.

Computer turns its self off on its ownaccord. Prevent By: Reboot.

5.Spam.

Unwanted emails that clog up your inbox. Cancontain viruses.

6.Viruses.

Install antivirus software and do scansregularly.

7.File loss

Save regularly and back up files on toexternal hard-drive.

8.Over Heating

clean out fan, make sure there’s no fabricstuck.

Mobile Technologies

Definition:

(advantages,what do we use it for? and features.)

1.Laptop/Netbook- Light, Compact and portable. Used on-the-go and canbe used away from a power source. Features: Lower Energy Consumption Hard Drive MemoryGraphics, Optical Discs

2. Smart Phones- Stay Connected, Keep in Touch, Organized, Business, Usedevery day by public, great for business. Features: Web Browser, Applications, Full Keyboard or Touch-screen, LargerScreen, Email

3.Palmtops/Tablets/PDA-Small, LightClever. Portable electronic organizers. Features: Organizer MP3 Playercontacts, calendar, email, word processor, Internet browser, WiFi, Camera.

The effects of Emerging Technologies.

Whatdifferences there are in society because of internet ect.?

There is not one part of life that is nottargeted by one sort of radical, new technology. The problem remains thatprivate firms that are developing these advances have every reason to promotetheir benefits and minimize their negatives. Nuclear power was once seen as aclean alternative to coal, for example. Only with time were the negativeimplications made clear. It should be noted that the potential risks of each ofthese technologies are substantial, and much work has and is being done toalert the public about their application in the future.

Computer Peripherals- Input, Output Devicesand Storage Devices.

Input Devices.

Keyboard

Keyboardsare a way to enter textand numerical data into acomputer.

Each individualkey is a switch, which when pressed, sends a digital code to the computer.

Specialized Keyboard

Mouse

The mouse is used to control themovement of a pointer on the screen when it is moved horizontally over a flatsurface.

A ball under the mouse rotates when it ismoved and turns two rods, one for left/right and one for up/down

Joystick

Joysticks are often used for playingcomputer games such as flight simulators. They can also be used to control themovement of a wheelchair or other machinery.

They input directional data like a mousebut work by switches being closed as the joystick is moved left or right and upor down.

Mini finger-controlled joysticks can beused to control a laptop cursor.

Tracker Ball

A tracker ballis used in the same way as a mouse but it is useful where desk space islimited.

It is like an upside down mouse becausethe user rotates the ball and the main body part stays still. It has buttonslike a standard mouse. Ideal for use where flat space close to the computer islimited.

Touch Pad

Microphone

This is used for the input of sound whichis then digitised by the computer. The digital audio can be saved for playbacklater on.

The digital audio can also be used withvoice-recognition software to control hardware, navigate a menu or input textinto a word processor. Voice recognition can also be used in securitysystems.

Remote Control

These emit a beam of infra-red lightwhich carries digital data signals. They are often used to control TV's andVCR's.

More advanced models can be programmed totransmit a series of commands with one button press.

Scanner

These are used to digitise images of pagesor objects.

A light moves slowly over the surface of the picture or object tobe scanned. The colours of the reflected light are detected and digitised tobuild up a digital image. The digital data can then be saved by a computer asan image file.
They can be used with OCR software to convert images of text into actual text datawhich can be edited by a word processor.

Digital Camera

These are used to take photographs like anormal camera but produce digital images instead of using film.

The light passing through the lens isdigitised by special lightsensitive sensors.The image is stored on memory chips in the camera and can then be transferredto a computer.

Web Cam

Touch Screen

Interactive White Board

Magnetic Stripe

Magnetic stripes are thin strips ofmagnetic tape which are usually found on the back of plastic credit and debitcards.

When the card is inserted into a reader (inan Automatic Teller Machine or ATM for example) the tapes slides past aplayback head similar to that used in a tape recorder. This reads the data fromthe stripe and passes it to a computer.

Sensor

These detect changes in the physical or chemicalenvironment and convert them into electrical signals. These signals can then bedigitised and used by the computer.

Sensors are often used when data logging.

Bar Code Reader

OMR Reader

OCR Reader

Graphics tablet

Midi System

MIDI stands for Musical InstrumentDigital Interface. These are normal musical instruments which have a MIDIport for input into a MIDI interface in the computer.

The notes are converted into digital dataand saved as a file on the computer. This data can be converted back intonotes or edited by computer software.

Output Devices.

Monitor

Printer(Laser/Inkjet)

Lazer

InkJet

Speakers

Projectors

Plotters.

(40% of exam.)