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Computer-based interactivity is about letting users become active. Interactivity implies
empowering users to control the environment by making choices while a presentation
unfolds and interact spontaneously with the information and objects presented to them.
Today, most online and offline environments offer interactivity at various levels, starting
with the most basic functionality, such as linear navigation (forwards and backwards, up-
wards and downwards) and non-linear navigation (hyperlinks), to more complex levels of
interactivity such as support features or object interactivity. However, the higher the degree
of interactivity, the less mature the systems. Non-immersive and immersive interactive
environments, such as virtual worlds, are still in a highly experimental stage and have not
yet reached a critical mass. In between are environments that offer higher degrees of
interactivity in rudimentary form, yet those systems still need improvement and more
intelligence to reduce complexity and increase user friendliness.
The following graphic gives a classification of the maturity of environments that offer
different levels of interactivity.
In contrast to offline environments, delivering high interactivity over the Internet faces
additional barriers with regard to the technological demands.The higher the degree of
interactivity, the higher the requirements on technology.While low level interactive systems
are mostly based on text and graphics alone which can be delivered through simple HTML
pages using a browser, high level interactivity can only be delivered through built-on
capabilities of the web and additional programming such as Java, JavaScript, cgi-script or
Active X. Online forms, for example, often use JavaScript to provide interactivity to the
form. In addition, to be able to deliver interactive multimedia, the built-in capabilities of the
web are no longer enough, but requires users to install additional small programmes, so
called plug-ins, to work in conjunction with the web browser. For example, an authoring
system uses a plug-in to launch the authoring environment. In this case, the user is no
longer totally within the web environment, but uses external modules to provide
interactivity. Clearly, this may cause additional barriers for users who do not want to install
additional software.
IX TECHNOLOGY
Maturity of systems with different interactivity levels
Maturity
Level of
interactivity
highly immature
immature
fairly immature
fairly mature
mature
highly mature
low
high
very high
Linear
interactivity
Hyperlinked
interactivity
Hierarchical
interactivity
Support
interactivity
Object
interactivity
Update
interactivity
Construct
interactivity
Reflective
interactivity
Non-immersive
interactivity
Immersive
interactivity
Works
Needs improvement
Needs more
research
Needs more
research
Source: Salzburg Research, 2001