Igcse Ict Unit 2

Front 1

What is an input device?

Back 1

A component or peripheral device (such as a barcode reader, graphic tablet, keyboard, magnetic-stripe reader, modem, mouse, scanner, or stylus) that feeds data or instruction into a computer for display, processing, storage, or outputting or transmission.

Front 2

What is an output device?

Back 2

Any peripheral that receives and/or displays output from a computer.

Front 3

What is the use of a mouse?

Back 3

The mouse is used to control the movement of a pointer on the screen when it is
moved horizontally over a flat surface.
A ball under the mouse rotates when it is moved and turns two rods, one for
left/right and one for up/down.
Buttons on the mouse let you select options from menus and drag objects around the
screen etc. Some models are now wireless.

Front 4

What is the use of a keyboard?

Back 4

The standard QWERTY keyboard is the commonest
way to enter text and numerical data into a
computer.
Each individual key is a switch, which when
pressed, sends a digital code to the computer.

Front 5

What is the use of a scanner?

Back 5

These are used to digitise images of pages or objects.
A light moves slowly over the surface of the picture or object to be
scanned. The colours of the reflected light are detected and digitised to
build up a digital image. The digital data can then be saved by a computer as an image file.

Front 6

What is a Magnetic Stripe Reader?

Back 6

Magnetic stripes are thin strips of magnetic tape which are usually
found on the back of plastic credit and debit cards.
When the card is inserted into a reader (in an Automatic Teller Machine
or ATM for example) the tapes slides past a playback head similar to
that used in a tape recorder. This reads the data from the stripe and
passes it to a computer.

Front 7

What are sensors?

Back 7

A sensor is a device that converts a real-world property (e.g. temperature) into data that a computer can process.

Front 8

What are remote controls?

Back 8

These emit a beam of infra-red light which carries digital data signals. They are often
used to control TV's and VCR's.
More advanced models can be programmed to transmit a series of commands with one
button press.

Front 9

What are monitors?

Back 9

The computer monitor (also known as a VDU or Visual Display Unit) is
the most common computer output device. For desktop computers,
cathode ray monitors (CRT) are gradually being replaced by flatscreen monitors such as the Liquid Crystal Displays (LCD) and Thin Film
Transistor (TFT) displays used with laptop computers because they use
less power and take up less space.

Front 10

What are printers?

Back 10

Printers produce a printed 'hard copy' on paper. Different printers are suited to different
purposes and have a range of purchase and running costs.

Front 11

What are the three main types of printers?

Back 11

Dot matrix printers, Ink-jet printers, and Laser printers.

Front 12

What are motors?

Back 12

Motors are not usually powered directly from a computer as they use too much current. They
are usually controlled through a relay which is an an electronic switch. In a relay a small current
controls an electromagnetic switch which can turn on or off the much larger current which
powers the motor.

Front 13

What is a PIN pad?

Back 13

This is a device with a numeric keypad used to enter a person’s Personal Identity Number (PIN) e.g. when paying with a credit card.

Front 14

What is a Tracker Ball?

Back 14

A pointing device found on most laptops. Used instead of a mouse since it takes up less space. The user moves a finger across the touch pad and this movement data is sent to the computer.

Front 15

What is a Touch Screen?

Back 15

A touch screen is an alternative to a separate pointing device. With a touch screen the user selects items on the screen by touching the surface. This makes touch screen systems very intuitive and simple to use.

Front 16

What is a Graphics Tablet?

Back 16

A pointing device often used by designers and artists to allow natural hand movements to be input to graphics applications.
A stylus is held like a pen and moved over the surface of the tablet. Data about the stylus movements are sent to the computer.

Front 17

What is a Web Cam?

Back 17

This is a very basic video camera used to feed live video into a computer.

The video data from a web cam is low quality compared to a full video camera. However it is good enough for web chats (e.g. using a messenger application such as MSN Messenger or Skype).

Front 18

What is a "Chip" Reader?

Back 18

A card is inserted into the reader where metal contacts connect to the metal pads on the front face of the card. The reader can then access the memory chip and the data stored on it.

Front 19

What is a MICR Reader?

Back 19

Magnetic Ink Character Recognition (MICR) is a technology that allows details from bank cheques to be read into a computer quickly and accurately.
The cheque number and bank account number are printed at the bottom of each bank cheque in special magnetic ink using a special font. These numbers can be detected by an MICR reader.

Front 20

What is an OMR Scanner?

Back 20

Optical Mark Recognition (OMR) is a technology that allows the data from a multiple-choice type form to be read quickly and accurately into a computer.
Special OMR forms are used which have spaces that can be coloured in (usually using a pencil). These marks can then be detected by an OMR scanner.

Front 21

What is a Barcode Reader?

Back 21

A barcode is simply a numeric code represented as a series of lines.
These lines can be read by a barcode reader/scanner.
The most common use of barcode readers is at Point-of-Sale (POS) in a shop. The code for each item to be purchased needs to be entered into the computer. Reading the barcode is far quicker and more accurate than typing in each code using a keypad.

Front 22

What is a Multimedia Projector?

Back 22

Digital projectors are used in situations when a very large viewing area is required. A projector connects to a computer, a DVD player or a satellite receiver just like a ordinary monitor.
The image is produced inside the device and then projected out through a large lens, using a powerful light source.

Front 23

What is a Plotter?

Back 23

Plotters create hard-copy in a very different way to printers. Instead of building up text and images from tiny dots, plotters draw on the paper using a pen.
The pens are held in an arm which can lift the pen up or down, and which can move across the paper. The arm and pen create a drawing just like a human could, but much more accurately and more quickly.

Front 24

What is a Control Actuator?

Back 24

An actuator is a device, controlled by a computer, that can affect the real-world.

Front 25

What are pumps?

Back 25

A pump is basically a motor attached to a device that can push water or air along pipes. When the motor is switched on, water or air flows along the pipes to places it is needed.

Front 26

What are buzzers?

Back 26

Buzzers can provide noise.