We believe that navigation in information spaces is best supported by tapping into our natural spatial and geographic ways of thinking. To this end, we are developing a new computer interface model called Pad. The ongoing Pad project uses a spatial metaphor for computer interface design. It provides an intuitive base for the support of such applications as electronic marketplaces, information services, and on-line collaboration. Pad is an infinite two-dimensional information plane that is shared among users, much as a network file system is shared. Objects are organized geographically; every object occupies a well defined region on the Pad surface. For navigation, Pad uses "portals" - magnifying glasses that can peer into and roam over different parts of this single infinite shared desktop; links to specific items are established and broken continually as the portal's view changes. Portals can recursively look onto other portals. This paradigm enables the sort of peripheral activity generally found in real phy...

We introduce a model for supporting collaborative work between people that are physically close to each other. We call this model Single Display Groupware (SDG). In this paper, we describe this model, comparing it to more traditional remote collaboration. We describe the requirements that SDG places on computer technology, and our understanding of the benefits and costs of SDG systems. Finally, we describe a prototype SDG system that we built and the results of a usability test we ran with 60 elementary school children. Keywords CSCW, Single Display Groupware, children, educational applications, input devices, Pad++, KidPad. INTRODUCTION In the early 1970's, researchers at Xerox PARC created an atmosphere in which they lived and worked with technology of the future. When the world's first personal computer, the Alto, was invented, it had only a single keyboard and mouse. This fundamental design legacy has carried through to nearly all modern computer systems. Although networks have...

Workspace awareness is knowledge about others’ interaction with a shared workspace. Groupware systems provide only limited information about other participants, often compromising workspace awareness. This paper describes a usability study of several widgets designed to help maintain awareness in a groupware workspace. These widgets include a miniature view, a radar view, a multiuser scrollbar, a glance function, and a “what you see is what I do ” view. The study examined the widgets’ information content, how easily people could interpret them, and whether they were useful or distracting. Observations, questionnaires, and interviews indicate that the miniature and radar displays are useful and valuable for tasks involving spatial manipulation of artifacts.

The rich person-to-person interaction afforded by shared physical workspaces allows people to maintain up-to-the minute knowledge about others ’ interaction with the workspace. This knowledge is workspace awareness, part of the glue that allows groups to collaborate effectively. In real-time groupware systems that provide a shared virtual workspace, the possibilities for interaction are impoverished when compared with physical workspaces, partly because support for workspace awareness has not generally been a priority in groupware design. In this paper, we present the concept of workspace awareness as one key to supporting the richness evident in face-to-face interaction. We construct a conceptual framework that describes the elements and mechanisms of workspace awareness, and then show several widgets that can be embedded in relaxed-WYSIWIS groupware systems to support the maintenance of workspace awareness.

Many information structures are represented as two-dimensional networks (connected graphs) of links and nodes. Because these networks tend to be large and quite complex, people often

This article is a substantially expanded version of a report presented at the 1998 ACM CHI conference [Gutwin and Greenberg 1998]. Authors' addresses: C. Gutwin, Department of Computer Science, University of Saskatchewan, 57 Campus Drive, Saskatoon, Saskatchewan S7N 5A9, Canada; email: gutwin@cs.usask.ca; S. Greenberg, Department of Computer Science, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada; email: saul@cpsc.ucalgary.ca. Permission to make digital / hard copy of part or all of this work for personal or classroom use is granted without fee provided that the copies are not made or distributed for profit or commercial advantage, the copyright notice, the title of the publication, and its date appear, and notice is given that copying is by permission of the ACM, Inc. To copy otherwise, to republish, to post on servers, or to redistribute to lists, requires prior specific permission and / or a fee

From a technological and human perspective, shared space in remote collaboration has tended to focus on shared space of either the people or the task. The former would be charac-terized by traditional video/teleconferencing or videophones. The latter could be characterized by synchronous computer conferencing or groupware. The focus of this presentation is the area where these two spaces meet and are integrated into what could be character-ized as video-enhanced computer conferencing or computer-enhanced video conferencing. From the behavioural perspective, the interest lies in how- in collaborative work- we make transitions between these two spaces. For example, in negotiating, the activity is mainly in the shared space of the participants themselves, where we are "reading " each other for information about trust and confidence. On the other hand, in preparing a budget using a shared electronic spreadsheet, for example, the visual channel is dominated by the task space. How well systems affords natural transitions between these spaces will have a large impact on their usability, usefulness, and acceptance. Consequently, we investigate the design space and some of the issues affecting it.

The promise and perplexity of multimedia-supported collaboration Multimedia technology promises to enable smooth and effective interactions among collaborators in different locations. The growing need to support technical and social activity that occurs across geographical distances has not been fully satisfied by the current technologies of phones, faxes, electronic mail, and video conference rooms. Visions of systems that allow people from around the world to see and hear each other have been promoted at least since AT&T unveiled the PicturePhone in the mid-1960's. Recent technology and infrastructure developments are adding to the promise of multimedia support for remote collaboration Research prototypes that provide what is often referred to as desktop conferencing (audio, video, and computational connections between computer desktops) have been demonstrated using analog However, increased costs (e.g., upgrading networks, buying media-equipped workstations) and uncertainty over the benefits of collaborative multimedia have been significant barriers to its widespread adoption and use. While videophone products have recently reappeared in the marketplace, the lack of commercial success of PicturePhone since it was introduced almost 30 years ago indicates that there is much yet to be learned about the deployment and use of collaborative multimedia technologies Furthermore, research to date on the effects of various communication media on collaborative activity has not provided convincing evidence of the intuitively presumed value of video

This dissertation analyzes the usefulness of existing "conventional" collaboration-transparency systems, which permit the shared use of legacy, single-user applications. I find that conventional collaboration-transparency systems do not use network resources efficiently, and they impose an inflexible, tightly coupled style of collaboration because they do not adequately support important groupware principles: concurrent work, relaxed WYSIWIS, group awareness, and inherently collaborative tasks. This dissertation proposes and explores solutions to those deficiencies. The primary goal of this work is to maintain the benefits of collaboration transparency while relieving some of its disadvantages. To that end, I present an alternate implementation approach that provides many features previously seen only in applications specifically designed to support cooperative work, called collaboration-aware applications. The new approach uses a replicated architecture, in which a copy of the application resides on each user's machine, and the users' input events are broadcast to each copy. I discuss solutions to certain key problems in replicated architectures, such as maintaining consistency, unanticipated sharing, supporting late-joiners, and replicating system resources (e.g., files, sockets, and random number generators). To enhance the collaborative usability of a legacy application, the new approach transparently replaces selected single-user interface objects with multi-user versions at runtime. There are four requirements of an application platform needed to implement this approach: process migration, run-time object replacement, dynamic binding, and the ability to intercept and introduce low-level user input events. As an instance of this approach, I describe its incorpor...

Groupware toolkits let developers build applications for synchronous and distributed computer-based conferencing. This chapter describes four components that we believe toolkits must provide. A run-time architecture automatically manages the creation, interconnection, and communications of both centralized and distributed processes that comprise conference sessions. A set of groupware programming abstractions allows developers to control the behavior of distributed processes, to take action on state changes, and to share relevant data. Groupware widgets let interface features of value to conference participants be added easily to groupware applications. Session managers let people create and manage their meetings and are built by developers to accommodate the group’s working style. We illustrate the many ways these components can be designed by drawing on our own experiences with GroupKit, and by reviewing approaches taken by other toolkit developers.