8. Dialogue and style of interface

We have discussed the typical options available for input, prompting and feedback. With a Human-Computer-Interface (HCI), the options you choose to use will guide the design of the overall HCI.

GUI Example: Preparing an online training course

Thinking about the user and the way they need to interact with the training package. A good choice of interface would be a Graphical User Interface. Consider these features

• GUIs are very familiar to most computer users, so it is simple to understand how it generally works. They are there to train, not to waste time figuring out the interface
• GUIs look attractive with colourful screens and icons for the user to interact with. Compare this to a stark old-style mainframe interface, it make the experience more pleasant.
• GUis are very flexible. The menus and icons can be as creative as need be.

CLI Example: Configuring a system with set values

Consider a proficient system administrator who wants to set up a server. They are completely familiar with what needs to be done. They just need an efficient way of doing it.

In this case a Command Line Interface (CLI) is a good choice. The administrator is presented with a prompt and he just needs to type in the correct commands to set up the server. The server does not even need a permanent display, so saving money, space and power. Logging in remotely to the machine via a CLI is a popular way of maintaining a server.

Form Example: Opening a savings account

Consider you are online and want to open a savings account. In this instance a specific set of information needs to be provided by the customer and only a minimal amount of technical knowledge is assumed ie. they can type.

In this case a form dialogue is a good option. The user is presented with hopefully an attractively formatted form consisting of input boxes, combo boxes, radio buttons, check boxes and so on. Behind the form will be data validation, error feedback and verification procedures. The form interface is an excellent choice when the dialagoue is mostly user input.

Natural language Example: Operating a phone in a car

In this instance there is a serious safety aspect to consider. You want to allow the driver to keep his hands on the wheel rather than fiddle with an interface. You also want him to keep his eyes on the road.

A natural language interface is an excellent option in this circumstance. To start off the dialogue he presses a single 'Listen to me' button on the steering wheel to activate the natural language dialogue. The system provides an audible prompt to indicate it is ready. The driver speaks his command such as "Phone Home" and that is it. The system then sets up the phone call and the driver simply talks.

Natural language interface does have difficulty with background noise, but in this instance the safety requirement over rides this disadvantage.

Conclusion

When developing an interface method, it is very important that the characteristics of the dialogue is considered. There are a number of interfaces available and each one should be considered on its merits.