The earliest speculations about communication with extraterrestrial intelligence (CETI) involved contact with the inhabitants of other bodies of our Solar System, either our Moon or other planets. Astronomical theories in the nineteenth century made plausible a belief in the prevalence of life on non-terrestrial worlds circling our Sun. When the focus turned to the possibility of communicating with the potential denizens of these worlds, their relative closeness to the Earth made it conceivable that signals could be detected through optical telescopes.

DESPITE MANY YEARS OF ADVANCES in computer graphics hardware and software, and in human interface technologies' designs, and styles, our user interfaces are still primarily static' The purpose of this chapter is to review ways in which dynamic imagery and animation have been used in interfaces to date, and to sketch some ways in which they could be used to enrich the interfaces of the future. Our thesis is that current uses of animation at the interface have barely scratched the surface of what is possible and interesting.

It is widely accepted that there exists a region or locus of maximal resource allocation in visual perception--sometimes referred to as the spotlight of attention. We have argued that even if there is a single locus of processing, there must be multiple loci of parallel access--several places in the visual field must be indexed at once and these indexes can be used to determine where attention is allocated. We have carried out a variety of studies to support these ideas, including experiments showing that subjects can track multiple independent moving targets in a field of identical distractors, that the enhanced ability to detect changes occurring on these targets does not accrue to nontargets nor to items lying inside the convex polygon that they form (so that a zoom-lens of attention does not fit the data). We have used a visual search paradigm to show that (serial or parallel) search can be confined to a subset of indexed items and the layout of these items is of little importance. We have also studied the phenomenon known as subitizing and have shown that subitizing occurs only when items can be preattentively individuated and in those cases location precuing has little effect, compared with when counting occurs, which suggests that subitizing may be carried out by counting active indexes rather than items in the visual field. And finally we have run studies showing that a certain motion effect that is sensitive to attention can occur at multiple precued loci. We believe that this evidence suggests that there is an early preattentive stage in vision where a small number of salient items in the visual field are indexed and thereby made readily accessible for a variety of visual tasks.

Does Animation helps build richer, more vivid, and more understandable visualizations, or simply confuse things?

In this paper, we describe an empirical investigation of the utility of several perceptual properties of motion in information-dense displays applied to notification. Notification relates to awareness and how dynamic information is communicated from the system to the user. Key to a notification technique is how easily the notification is detected and identified. Our initial studies show that icons with simple motions, termed moticons, are effective coding techniques for notification and in fact are often better detected and identified than colour and shape codes, especially in the periphery. A subsequent experiment compared the detection and distraction effects of different motion types in several task conditions. Our results reveal how different attributes of motion contribute to detection, identification and distraction and provide initial guidelines on how motion codes can be designed to support awareness in information-rich interfaces while minimizing unwanted side effects of distraction and irritation.

The proliferation of information on the Internet poses a significant challenge on humans' limited attentional resources. To attract online users' attention, various kinds of animation are widely used on websites. Despite the ubiquitous use of animation, there is an inadequate understanding of its effect on attention. Focusing on flash animation, this study examines its effects on online users' performance and perceptions in both taskrelevant and task-irrelevant information search contexts by drawing on the visual search literature and two theories from cognitive psychology. In the task-relevant context, flash is applied on the search target; while in the task-irrelevant context, flash is applied on a nontarget item. The results of this study confirm that flash does attract users' attention and facilitates quicker location of the flashed target item in tightly packed screen displays. However, there is no evidence that attracting attention increases recall of the flashed item, as is generally presumed in practice, and may even decrease the overall recall. One explanation is that when users have to use their limited attentional resources on suppressing the distraction of flash, they will have less mental resources to process information. Moreover, the results suggest that processing information about an item depends not only on the attention it attracts per se, but also on the attention that other items on the same screen attract. While flashing an item may not increase the recall of that item, it can reduce the recall of other items (especially the nontarget items) on the screen. Finally, flash has negative effects on users' focused attention and attitude towards using the website. These results have implications for website interface design, online product promotion, online advertising, and multimedia training systems, among others.

Direct manipulation has been lauded as a good form of interface design, and some interfaces that have this property have been well received by users. In this article we seek a cognitive account of both the advantages and disadvantages of direct manipulation interfaces. We identify two underlying phenomena that give rise to the feeling of directness. One deals with the information processing distance between the user's intentions and the facilities provided by the machine. Reduction of this distance makes the interface feel direct by reducing the effort required of the user to accomplish goals. The second phenomenon concerns the relation between the input and output vocabularies of the interface language. In particular, direct manipulation requires that the system provide representations of objects that behave as if they are the objects themselves. This provides the feeling of directness of manipulation.

Design helps the systems of daily life run smoothly, letting users and readers ignore how things are put together. Design should sometimes announce itself in order to shed light on the system, exposing its construction, identity, personality, and politics.

Type on Screen: an uneasy relationship from the beginning

If you think it’s crowded now, just wait! The Web is heading toward its own year-end calamity unless some skillful maneuvering is applied — quickly.

Animations are seen in many web sites throughout the Internet. Ease of use is considered as a possible reason for the growing use such multimedia feature in designing of web sites. While animations are ubiquitous in the Web environment, there is an inadequate understanding of its effect on user's attention. Animations are advantages of information technology for web designers, but important questions remain about whether animations work in all situations and for all users. Focusing on web animation, this paper reviews literature and at the end it extracts guide lines for better designing of websites.

User interfaces are often based on static presentations, a model ill-suited for conveying change. Consequently, events on the screen frequently startle and confuse users.

Animation can be a very effective mechanism to convey information in visualization and user interface settings. However, integrating animated presentations into user interfaces has typically been a difficult task since, to date, there has been little or no explicit support for animation in window systems or user interface toolkits. This paper describes how the Artkit user interface toolkit has been extended with new animation support abstractions designed to overcome this problem.