The interaction between users and personal computers had one of its major milestones in the 80s, with the wide spread marketing of systems equipped with user interfaces based on the so called desktop metaphor (Kaptelinin & Czerwinski, 2007a). The desktop metaphor is based on the idea that applications and documents can be managed within a “space” organized as a desktop, coupled with a storage system based on the concept of folders containing files. Moreover, the desktop metaphor is characterized by the possibility of representing active applications as overlapping windows, usually referred to by small icons (Kaptelinin & Czerwinski, 2007a).
The desktop metaphor (Smith et al., 1982) was conceived for individual users of stand-alone personal computers, mainly to support them in running applications and storing/retrieving documents. Then, the 90s brought the Internet and the Web: users started using Web browsers to navigate Web sites and to store bookmarks, as well as email, chats and forums to interact with other users. Later on, at the beginning of the new millennium, the so called Web 2.0 (O'Really, 2007) further modified the way people interact with computers. Web sites became much more interactive and stand-alone applications were replaced by Web-based services; users were encouraged to participate in content creation on the Web through blogs, wikis, tagging systems, and to collaborate by means of social networks and Web-based collaborative tools. Last but not least, service access became ubiquitous, services are available in a anywhere and anytime modality, and can be accessed by a variety of devices, like laptops, tablets, and smart phones. The recent development of the cloud computing paradigm (Creeger, 2003) is the last step in this direction, further supporting information and knowledge sharing on the Net and offering the possibility of storing documents, data, and resources in the Cloud.
All these changes definitely modified (a) the user role, who is not an “individual user” anymore, but is “dipped” into a fluid community of users; (b) applications, which are not stand-alone programs running on local machines, but Web/Cloud-based services; (c) file storage and retrieval, which has been replaced by the need of handling many heterogeneous types of “objects” (not only files, but emails, posts, events, bookmarks, contacts, etc.); (d) the personal computer itself, which evolved in a range of personal mobile devices. However, the desktop metaphor is still there. There have been many proposals, in the research literature, to go beyond it, in order to face the challenges posed by the various aspects of the just mentioned evolution; see (Kaptelinin & Czerwinski, 2007b) and Related Work Section of this paper. But, so far, none of them has been able to stand out and actually replace the desktop metaphor.