GNVQ ICT - Intermediate
Unit 3 - Hardware and Software
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GNVQ ICT - Intermediate Unit 3 - Hardware and Software
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Input devicesBarcode reader
Barcodes are different groups of vertical bars that can be read by an optical scanner. Barcodes are printed on nearly every product that you can buy. Shops use barcodes because they are cheap to produce and very durable. Concept keyboard
A concept keyboard is a flat board that contains a grid of buttons. Each button can be programmed to follow instructions. An overlay sheet is placed on the grid with an explanation for each button. They are used in primary schools with young children. Many modern fast food restaurants and pubs have overlays with either a description or picture of the meals/drinks that are available to make ordering easier. Digital camera
A digital camera allows you to take pictures and to store a digital photographic image that can be read by a computer. You can then transfer the images directly from your camera on to your computer. Digital cameras may be used, for example, by estate agents for producing advertising and sales material. Graphics tablet
A graphics tablet consists of a flat pad (the tablet) on which the user draws with a special pen. As the user draws on the pad the image is created on the screen. Using a graphics tablet a designer can produce very accurate on-screen drawings. Joystick
This works in similar way to a mouse but is usually used for playing action games. The "fire" button or trigger is used to shoot at the targets provided in the game. Keyboard
The commonest way to enter data into a computer. Each key
is simply a switch, which when pressed, results in a digital code being sent to
the computer. For example, pressing the 'A' key produces the code 01100001
representing the lower case letter 'a'. Holding down the shift key at the same
time produces the code 01000001 representing the upper case letter 'A'. Light Pen
The pen works directly on the screen. Touch
sensitive screens and electronic whiteboards that respond to the touch of a
finger are now replacing these. MICR
(Magnetic Ink Character Reader)
Magnetic ink characters are the strange looking numbers that appear at the bottom of cheques. These characters are used because they are very difficult to forge or damage. Banks use MICR to read the numbers from the bottom of cheques to obtain data such as account numbers and bank sort codes. Magnetic strip
Magnetic strips are built into many plastic cards such as cheque guarantee cards, cash-point cards and personal identity cards. The magnetic strip on the back of the card can hold the personal details of the card owner and, with the necessary PIN, will allow access to secure information e.g. bank account details. MIDI (Musical Instrument Digital Interface)
A MIDI port (situated on the back of most computer systems) allows you to attach a musical instrument to your computer, for example a musical keyboard. You can then store a musical sequence on a computer and then have the computer play it back to you – either through speakers OR through the keyboard. When a MIDI port is used to playback the file it is working not as an input device but as an output device. ModemNOTE: A Modem is both an input AND an output device. The Internet is a huge Wide Area Network (WAN) where computers are linked using a variety of different connections. Most commonly a user has a device called a modem installed in their computer. This device converts the digital data used by the computer into analog data (sounds) that can be sent along a telephone line (rather like the noise a fax machine makes when sending a document to another fax machine). The modem dials a special number belonging to an Internet Service Provider (ISP). A modem inside the ISP’s computer converts the analog data back into digital form and, once the ISP’s database has checked the username and password of the user, a connection to the Internet is made. A modem can also be used as an answerphone.
Using some additional software, a user can set up a "voicemail" system
- giving the caller some alternatives - and the caller will respond by pressing
certain buttons on their telephone keypad. This will help them to get
through to the person or department they need. In addition, a modem can
sometimes be used as a fax machine - to send and receive faxes. Mouse
The movement of the mouse over a flat surface is mirrored by a pointer on the monitor screen. Under the mouse is a ball which rolls and turns two shafts, one for each direction - left/right & up/down. Buttons on the mouse enable selections to be made from menus, movement of objects around the screen, and painting or drawing. OMR (Optical Mark Reader)An optical mark reader reads marks made by pencil on a printed form into the computer. OMR systems are suited to reading pre-printed forms and check boxes such as National Lottery number selection sheets and multiple-choice exam papers. Scanner
Scanners are now a cheap and common way of getting images into a computer. They can also be used with OCR (Optical Character Recognition) software to scan in text. Sensors
Chemical responses to the physical
environment or movement can be converted to electrical signals in the sensor
that can be translated and used by the computer. Various sensors can be used to
measure heat, light, sound, pressure, strain, acidity (pH), oxygen
concentration, humidity, pulse, water level, water flow, speed, tilt or simply
whether something like a door or a valve is open or shut. Touch screenA touch screen is a special type of VDU, which has a grid of light beams or fine wires criss-crossing the screen. When the screen is touched (usually to choose an on-screen option), the computer senses where you have pressed. Due to the vast amount of information they can store, touch screen operated computers are generally used in the provision of public information and are found in places such as airports. Video digitiserA video digitiser takes an image from a video camera or television and converts it so that it can be used by, and stored on, a computer. Video sequences captured using a video digitiser are often used in multimedia presentations. Voice recognition (microphone)A microphone is used with a voice recognition system. This can be used with a word processing program to enter text. It can also be used as part of security systems - only certain digitally stored voices have access. |
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© Hyde Technology School - Non-commercial use by other educational establishments is welcome. Please email your comments to mail@ictgnvq.org.uk Created by K C Parry - Please email your comments to kcparry@ictgnvq.org.uk |
