Piles, Tabs and Overlaps in Navigation among Documents Mikkel Rønne Jakobsen and Kasper Hornbæk Department of Computer Science, University of Copenhagen Njalsgade 128, Building 24, 5th floor, DK-2300 Copenhagen, Denmark {mikkelrj, kash}@diku.dk ABSTRACT Navigation among documents is a frequent, but ill supported activity. Overlapping or tabbed documents are widespread, but they offer limited visibility of their content. We explore variations on navigation support: arranging documents with tabs, as overlapping windows, and in piles. In an experiment we compared 11 participants’ navigation with these variations and found strong task effects. Overall, overlapping windows were preferred and their structured layout worked well with some tasks. Surprisingly, tabbed documents were efficient in tasks requiring simply finding a document. Piled documents worked well for tasks that involved visual features of the documents, but the utility of recency or stable ordering of documents was task dependent. Based on the results, we discuss the effects of spatial arrangement, visibility, and task-dependency, and suggest areas for future research on document navigation and its support by piling. Author Keywords Document navigation, window switching, overlapping windows, piled windows. ACM Classification Keywords H.5.2 User Interfaces (D.2.2, H.1.2, I.3.6): Graphical user interfaces (GUI). INTRODUCTION Users frequently navigate between multiple documents, for instance to copy-paste text, compare web pages, or capture notes when reading. But navigation between documents is hard. Multiple windows or tabs are increasingly used in web browsing, for example, but users find it hard to manage multiple web pages [31]. In programming, source files are often viewed one at a time, requiring frequent navigation between files. Tabbed document interfaces that are common in widespread programming environments, such as Eclipse and Visual Studio, make navigating among many source files cumbersome [21]. Much research has aimed at supporting general window switching and switching between tasks or activities. General window switching techniques [26,29] help switching between applications, which are often visually distinct. However, switching between documents often takes place within one application and documents switched between may be visually similar. Also, while users’ frequent switching between tasks or activities needs support [7,18,27,28,30], often users must switch between multiple documents related to one task. Problems with existing switching mechanisms One facility for supporting navigation among documents is overlapping windows, standard in most operating systems. Hutchings et al. [19] found that 78% of the time people had eight or more windows open, making locating a particular window within a group of overlapping windows difficult. Switching between windows using the taskbar is also hard because users may only see a short part of the windows’ titles and because the taskbar occasionally collapses documents into one tile [13]. Another facility, using tabs to represent multiple documents within a single window, is seen in many web browsers, spreadsheets, and programming environments. But tabbed interfaces can only show a limited number of documents at any time, necessitating further interaction with scrollbars or drop-down lists. When several documents are open, tabs provide minimal visual cues for finding a particular Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. NordiCHI 2010, October 16–20, 2010, Reykjavik, Iceland. Copyright 2010 ACM ISBN: 978-1-60558-934-3...$5.00. Figure 1: Interface with two piles of spatially arranged documents. Figure 1: Interface with two piles of spatially arranged documents.