• Screens, CRT & TFT Monitor
• Digital projectors, interactive whiteboards, plasma screens
• Mobile Phone screens, PDAs
• Laser, Inkjet, Multi-function and Dot-matrix Printers, Plotters, Professional Printers, Photo printing
• Speakers

• Screens & Monitors
• CRT Monitor
• TFT Monitor

• Most PC systems are connected to a monitor, so that users can see what's happening
• Monitors arae able to display moving images
• Quality depends on its size and its resolution

• Based on cathode ray tubes that fire electrons at a screen to make each pixel glow in the correct colour
• Cathode ray tubes means CRT monitors are deep & take up a lot of room
• They give clear, sharp displays at low cost

• Monitors are much flatter, take up less space than CRT
• Use liquid crystals to form the image
• Small in size, which makes them extremely popular

• Digital Projectors
• Interactive Whiteboards
• Plasma Screen

• Used to project a large version of the monitor output
• Used in classrooms & businesses presentations
• Can be portable, but often celing mounted so that they don't need to be set up each time they are used

• Have a touch-sentitive surface that can be 'written on' using a stylus shaped (e.g. marker pen or finger)
• Often used in classrooms to allow students to share ideas and take part in interactive activities
• Handwriting recognition can be used to convert handwritten text to computer text
• Work produced can be saved and printed
• They are both input and output devices

• Often used as TVs, but can be used instead of normal computer monitors in public areas, e.g. shopping centres, reception areas of a business
• Work by illuminating tiny fluorescent lights to make an image
• Available in very large sizes

• Mobile phone screens
• PDAs

• People are using their phones to check emails, weather, travelling instructions or football scores
• 3G phones can display live, so need a good quality images which refreshes quickly
• Webe designers need to design webpage content which is useable in a small area
• Many TV companies allow phone users to download content that can be viewed/listened to on mobile devices

• Have a larger screen than mobile devices
• Users expect to be able to run application software (e.g. word processor, spreadsheets)
• Means that the user has to scroll around to see large documents, but designers try to keep this to a minimum by designing screen layouts carefully
• Usually have touch screens and a virtual keyboard that is operated by a stylus

• Laser
• Inkjet
• Multi-function
• Dot-matrix
• Plotters

• Print a full page at a time like a photocopier
• Monochrome laser, popular in offices & other situations where they need high-quality documents printed quickly = colour isn't very important
• Colour laser printer have become less expensive to buy
• Colour laser printers produce clear text & diagrams
• Photographs are limited in quality compared to high resolution inkjet printers

• Very popular in the home because they tend to be cheaper to buy than lasers, although can be expensive to run
• Better than lasers for printing photographs because has more than the basic three colours in the high resolution printer

• Include built in scanner
• Can be used as a simple Photocopier
• Suitable for home or small office
• Often have fax facilities
• Usually use inkjet rather than laser

• Print on multipart stationary
• Used infrequently now as other printing methods have become cheaper & faster than dot-matrix technology
• Some cash tills in shops use small dot-matrix and multipart stationary to produce a copy of the receipt

• Used mostly to print large sized technical drawings
• Smaller models are available for drawing graphs
• Many engineers and architects now use very large inkjet printers rather than plotters for printing out plans & drawings on paper upto A0 size
• Extremely expensive to buy
• Only used for specialist purposes
• Able to produce full-colour graphics

Speakers

• External speakers are plugged into the computer & play sounds
• They vary in size, quality, appearence & level of volume they produce 
• Many monitor & laptops have built in speakers. They are relatively low quality, suitable for general purposes but not high enough for high quality music/some game players
• Limited in volume; designed for personal use

• What kind of image needs to be viewed?
• Where is it going to be viewed?
• Who is going to view the image?
• Internet access

• What is to be printed?
• How many documents?
• What kind of media?
• Who is to use the printer?