Interacting with IT Systems

Fundamentals of Information TechnologySession 5

Interaction

• Interaction is process of communication that involves two or more participants

dialogue

multilogue

Interaction

• Interaction can be understood as a form of request/response communication

1. A sends a request to B2. B sends a response to A

A B

12.30pmWhat time is it?

Interaction

• Successful interaction requires a shared language of communication

• Successful interaction requires a shared set of rules

A B

晋语What time is it?

A B

Give me the time

now!

What a rude person!

Interaction

• In an interactive exchange, participants have a measurable effect upon one another so that in the process of the interaction the status of both is changed.

• Both A and B now know the time• A knows B is a reliable source of time information• B knows A does not have a watch

A B

12.30pmWhat time is it?

I’m late for the dentist!

Interactivity

• Interaction also occurs between human beings and computer programs.

• The extent to which a computer program allows interaction is known as its interactivity

• Some computer programs have high levels of interactivity (e.g. games); others have little or no interactivity (e.g. embedded systems)

HighLow

gamesVirtual reality

Embedded systems

How interactive is the Web ?

Interactive and non-interactive elements of

interfaces

What are the interactive and non-interactive elements on the Guardian homepage?

Interactivity

• Interactivity is facilitated through a combination of hardware and software elements of an IT System

Hardware Software

Mouse (input) Graphical user interface

Keyboard (input)

Speakers (output)

Monitor (output)

?

Graphical User Interface

• Originally, interaction with computers was achieved through a text-based command line interface (e.g. DOS or Telnet)

• Now, apart from specialist or embedded systems, human-computer interaction (HCI) is facilitated through the use of graphical user interfaces (GUI)

Graphical User Interface

• Standard graphical user interfaces are constructed from combinations of several classes of component – Menus– Controls

(buttons, combo boxes, etc)

– Display – Status

information

Graphical User Interface

• Common GUI controls

•What is each one called?

•What is each one used for?

Black

White

United Kingdom

Submit

Mr.Mrs.Miss.Dr.

Blue

Red

Green

Enter TextEnter More Text

sales orders enquiries

Designing a GUI for a Home Control System

• Identify each element (module) of the system

• Identify the user requirements for the (module) interface– Switch on all lights– Switch off all lights – Switch on light groups– Switch off light groups– Control brightness of all lights – . . . .

Control Panel

KitchenLiving Room Bedroom 1

LightsHeating Appliances

Designing a GUI for a Home Control System

• Storyboard the interfaceHeating AppliancesLights

On/offLight Group

Brightness

All lightsOn/off

Brightness

Fireside Spots

Maintenance

Fireside Spot 2 Change bulb

• Use Visio or a similar drawing tool to create a storyboard or mock-up of the interface

• Consider alternatives

• Make adjustments as necessary

Designing a GUI for a Home Control System

• Design the Menus – Consideration must be given to

• Conformance to standards – Windows standards for PC applications– Web standards for web applications

• Grouping (associating common elements)• Weighting (giving precedence to more commonly used

elements)

NewOpenCloseSaveSave AsPrint

UndoCopyCutPasteClearSelect all

File Edit

New Lighting Template

Insert

User-centred Design

• Many GUIs are too complex or inappropriate for their intended target audience and fail as a result

• This is often because end-users of IT systems are not consulted in the design process

• User-centred design puts the user at the centre of the design process

• By involving end-users of a system on a regular basis designers can properly understand the needs that the system is meant to satisfy

• User-centred design helps designers to properly tailor and maximize usability

• User centred-design methodologies include, observations, prototyping, user-testing, heuristic evaluation

(e.g. http://www.useit.com/papers/heuristic/heuristic_list.html )

Usability

• Usability is a quality attribute that assesses how easy user interfaces are to use.

• Usability can be defined by five quality components: – Learnability: How easy is it for users to accomplish basic

tasks the first time they encounter the design? – Efficiency: Once users have learned the design, how quickly

can they complete the tasks they need to do? – Memorability: When users return to the design after a

period of not using it, how easily can they re-establish proficiency?

– Errors: How many errors do users make, how severe are these errors, and how easily can they recover from the errors?

– Satisfaction: How pleasant is it to use the design?

Usability

• Usability considerations should inform all stages of software development

• Development– Focus groups – Paper prototyping

• Testing– Performance testing (quantifiable metrics)

• Number of clicks required to perform a task• Time taken to perform a task• Number of errors made by users• Frequency of failure to complete a task

– Think aloud protocol– Cognitive walkthrough

Accessibility

• Accessibility is closely related to usability – Determines how easy it is for people with disabilities

(e.g. blindness, dyslexia, colour blindness) to successfully make use of a piece of software

– Accessibility is a particular issue on the Web as a result of the demands of the Equality Act 2010 (Replacing the Disability Discrimination Act (DDA) 1998)

– Web content accessibility is measured against the Web Content Accessibility Guidelines (WCAG)

– The guidelines deal with issues such as• Navigation • Readability• Page layout • Use of colour

User Manuals

• User manuals are essential elements for first time users and for advanced users doing more advanced tasks

• Quality documentation reduces user errors and cuts out the need for after sales support

• A user manual should comprise: – An overview of system elements– Task instructions: a detailed, step-by-step breakdown of

how to complete individual tasks – A list of typical errors and how to recover from those

errors – A glossary of terms

User Manuals

• An extract from a typical user manual

FIT Session 5 – Activities

• Now do – Activity 5 – Interacting with IT systems