Topic 20: HCI

Topic 20: HCI

1. Operating Systems

   • Operating Systems are the programs that control the running of the computer. OS are software that is used to directly control the hardware and to run the application software.
   • Functions of Operating Systems: ~ Manage and control devices, ~ Deal with errors, ~ Handle the storage of data, ~ Maximize memory use, ~ Automatically recognise new hardware, ~ Provide a user interface.

2. Interfaces

   • An interface is where 2 things meet.
   • HCI stands for human computer interface.

3. Command Line Interface

   • Advantages: ~ Instructions are executed quickly, ~ Use less memory compared to other OS, ~ Quicker to type commands, ~ Little processing power is needed/used.
   • Disadvantages: ~ Difficult to learn, ~ Mistyping commands results in errors, ~ Some commands are very complex.

4. Graphical User Interface

   • Graphical User Interfaces use WIMP (windows, icons, menus and pointers)
   • Advantages: ~ Low level skills needed to use, ~ Pictures are multilingual, ~ Online tutorials, ~ Customised DTE.
   • Disadvantages: ~ May run slow as there are lots of things to process, ~ more memory is need (older computers will need to be updated), ~ Can be costly as faster processors are needed.

5. Voice/Speech Interface

   • Advantages: ~Useful for a user who is unable to use their hands, ~Speech input is much faster than keyboard input, ~People with a disability that prevents typing can use speech input, ~Less risk of RSI
   • Disadvantages: ~Its difficult for a computer to interpret accents, tones and pitch etc, ~language variations

6. Menus & Dialogue Boxes

   • Advantages: ~Easy to navigate, ~Nothing to learn, ~Little processing power needed, ~Ideal for beginners, ~No need to learn lots of commands
   • Disadvantages: ~Some options may not mean much to a novice user, ~Difficult to find options if there are lots of sub menus

7. Touch Sensitive Application

   • Advantages: ~No keyboard or mouse is needed so it saves desktop space, ~Easier or faster to use as the user simply touches what they see on the display, ~ a touch screen is very intuative
   • Disadvantages: ~Difficult to use or read if the display screen is dirty, ~Reflection and glare may prevent you from using it in certain environments

8. Biometrics

   • Advantages: No password or cards to forget, ~Difficult to pretend to be someone else, ~Biometric properties cannot be shared
   • Disadvantages: ~Some people may not possess the physical characteristics being measured, ~Possibility in human error when originally recording the data