Aims:

1. Aims: • Understand the need to facilitate an effective dialogue between humans and machines. • Explain the need to design systems which are appropriate to users at all levels and in different environments; the impact of clarity of structure and layout. • Describe how the user-interface can be designed for effective communication with the user. • Describe the advantages of common user interfaces between different generic application packages. • Describe the advantages and limitations of a natural language interface.

2. What is a HCI? • The interaction between a user and a computer. • The method by which the user tells the computer what to do, and the responses the computer makes. • May apply not only to PCs, but to any type of ‘computer’. Why do we need good interface design? • It can make a system more efficient. • Means that tasks can be accomplished effectively. • Helps to ensure safety in operation. • Makes the users’ interaction with the system more enjoyable.

3. How do I design a good user interface? Consider the following: • WHO will use the system. • WHAT type of task is being performed. • WHERE the computer is being used. • WHAT is technologically feasible.

4. Designing for the user • Interface should generally conform to the traditional Windows approach. • Splash Screens • Form providing instant feedback for the user, whilst hiding all the things going on in the background. E.g. whilst loading. • Provide feedback during any lengthy process. • Allow users to confirm or undo actions. • Be forgiving! • Make the interface simple and easy to use!

5. Placing the user in control • Provide multiple access methods. • Different ways of doing things, e.g. choosing from menus, command buttons, etc. • Access to both mouse and keyboard users. • Use standard menu items. • Experienced users of a Windows interface will expect to find standard menus and menu items. • Microsoft has defined 17 standard menu items that Windows applications should implement. • (File, Edit, Help menus, and menu items.) • Allow for non-linear use.

6. Planning for all users Making an application user-friendly to all users: • Do not rely on sound alone for any situation that requires attracting the user’s attention. • Do not rely on colour to convey information. • Do not require rapid response to a prompt. • Do not use flashing design elements. • Allow for non-mouse users. • Allow for screen reader software.

7. Advantages of a common user interface • Increased speed of learning. • Ease of use. • Confidence building for novice users. • Increased range of tasks solvable by experienced users. • Greater range of software accessible to the average user.

8. Visual Consistency • Internal consistency • Consistency within your application, e.g. same style on all dialogue boxes. • Suite consistency • Consistency among all the applications you deliver, so that users can easily move from one to another (e.g. MS Office). • Environmental consistency • Consistency with the rest of Windows.

9. Activity in MS Word • In MS Word, take a screen shot of a blank document. • Paste this image into Word, and use the drawing toolbar to label the following features: • Title bar • Vertical scroll bar • Horizontal scroll bar • Minimise button • Maximise button • Toolbar • Menu bar • For each feature, write a paragraph explaining how it is used to provide a user friendly interface.

10. Interface Styles: There are different approaches to the problem of communication with computers, including the use of; • Command languages • Forms and dialogue boxes • Menus • Graphic User Interface (GUI) • Natural language interface.

11. Command-line interface • First interactive dialogue style. • Still widely used. • Expresses instructions by means of single characters, words or abbreviations. • Users must know the necessary commands and syntax. (Difficult for a novice user.) • E.g. format a: , dir • Can be quick and efficient.

12. Forms and dialogue boxes • Often used for data entry. • Data Labels giving assistance • Boxes to enter/choose data • Making choices is easier - The user is given choices • Useful for novice users • Dialogue boxes are a special type of form, e.g.

13. Designing Forms • Display should have a title. • Avoid clutter. • Indicate the number of characters to be entered. • Option to make corrections. • Items should be in logical sequence. • Default values in place. • Careful use of colour, animation, etc. • Exit and help facilities.

14. Exam Question A railway station has a computer-based timetable enquiry system for use by passengers. Enquiries are entered from a keyboard and displayed on the screen-based form illustrated below. Details of the train times are displayed at the bottom of the screen. (a) The exact format of the input required for this system is not clear. Redesign the form to make it clear. (4) (b) Some users of the enquiry system find it difficult to use. Suggest three ways in which it could be made easier to use. (3) Destination: Date of Travel: Latest arrival time:

15. Menus For example: • Full screen menu (often used for a front end). • Pull-down menu. • Pop-up menu. Allow the user to choose one of a set of predefined operations.

16. WIMP interface (Windows, Icons, Menus, Pointer) • Window • Area through which a piece of software or data file may be viewed. • Several may be on screen at once. • May be moved, resized, tiled, stacked etc. • Mimics an office desk. • Icon • Small representative picture of a command / software. • Point and click to select it. • Menus (pull-down menus) • Pointer (mouse)

17. Graphical user interface (GUI) • Gives user control of the interaction with the program. • Another name for a WIMP interface. • Uses Windows, Icons, Menus and a Pointer. • Intuitive type of interface. Touch Screen • Allows user to enter commands or data by touching an area of the screen. • Used in fast food outlets, tourist information centres, etc.

18. Natural Language • User types or speaks in normal everyday language and the computer responds • Used in Microsoft Help and Ask Jeeves Web Site • Useful for novice users as they do not need to understand the computer to use it. • With vocal input, useful for physically disabled people.

19. Speech input / voice recognition • Command and control systems • Relatively small and cheap. • Small, tightly defined vocabulary of technical terms. • Computer may be ‘trained’ by user(s). • Large vocabulary dictation systems • Can handle whole sentences and extensive vocabularies. • Much greater processing power and memory space. • Still expensive and not in widespread use.

20. Exam Question A different human-machine interface would be needed for each of the following users: (i) a young child in a primary school; (ii) a blind person; (iii) a graphic artist. For each user describe and justify an appropriate human-machine interface. (9)

21. Applying User Interfaces to Users • Different users have different requirements: • Visually Impaired: • Mouse tails, screen magnified, contrasting colour schemes, large icons etc. • Expert users: • Command line, short cut keys, programming add ons • Location: • Touch screen interface, concept keyboard etc • Physically disabled: • Additional input devices require changes to the user interface

22. For the following examples of interface styles; • state what type of interface it is, and • list a benefit and a drawback of each.