Chapter 26 - The User Interface

Chapter 26 - The User Interface

1. main features of a command line interface

   • There is a prescribed list of command words Each command has its own syntax ... including a short word, The user inputs the specific command at a prompt Some commands require parameters or switches

2. main features of a form driven interface.

   • The screen layouts reflect existing data entry forms Data input boxes in the same positions Screens displaying the same text and instructions The user may be able to tick boxes. The user may navigate using BACK/NEXT/SAVE/EDIT buttons Validation/verification will be carried out. The order in which they complete the form may be controlled

3. Purpose of the user interface.

   • To accept input from the user To provide output for the user

4. main features of a natural language interface

   • Allows user to interact using written or spoken ‘human’ language, The user’s commands are compared with a database of sounds using speech recognition software Verbs or phrases are used to instigate functionality such as creating, modifying or selecting data

5. psychological factors which should be considered during the design of a user interface

   • Perception - experiences or intuition can influence how users perceive objects. This can influence the use of metaphors/icons
   • Memory - How humans retain and recall information including long-term/short-term memory. The memory load on the user should be kept to a minimum so verload should be avoided

6. main features of a graphical user interface

   • It uses windows Each window represents different applications/tasks These can be opened/closed/minimised by the user
   • It uses icons An icon is an image which suggests an application/task The user clicks on the icon to start the application/perform the task
   • It uses menus/submenus Each menu presents a series of options The user selects the required option
   • It uses a pointer which the user moves using a mouse/tracker ball to select an icon/menu option/window option
   • pull-down menus to provide options . . . buttons to provide functionality . . . scroll bars to assist navigation through screens/lists . . . icons to represent objects such as programs, folders . . . wizards to assist . . . a mouse to control a pointer
   • WYSIWYG

7. Features of a GUI to assist experienced users

   • Could include shortcuts like crtl s for save
     • could include function keys special keys programmed to carry out specific tasks
       • The interface could include a CLI so that commands can be entered as text
         • able to customise the interface by adding icons, shortcuts

8. Why expericened prefer CLI

   • memorised all the commands … so a CLI is a very direct method . NLI is relatively slow and prone to error

9. Why Touchscreen might be prefered by members of public

   • This interface does not require keyboard skills/ … and so can be used by “members of the public”
     • interface is durable it hasno moving parts and can be kept hygienic
       • Icons can be used to facilitate those of different languages

10. factors which influence human interaction with computer systems

    • Ergonomic factors Concerns the design of the general working environment and input devices Examples: adjustable chairs/split keyboards
    • Psychological factors Consider how humans learn and precieve things like long/short term memory
      • Use of common interfaces to reduce time taken to adapt and reduce the training time

11. Prompt - A message that indicates the point of inputs

12. Parameters - Refers to additional information required for the command

13. Ergonomic Keyboards - Specifically designed to be comfortable to use. May be split in two with integrated wrist or palm support. It enables a more natural posture and less finger effort