Although the text entries of the UEE are written in English, users can choose one of four access languages. Arabic pull-down menus give access to the brief identifications (fact files) in Arabic. French and German pull-down menus transfer the reader to the full entries in English. In order to interest less computer-savvy colleagues the UEE offers a very basic search option that stays closely to the look and feel of a traditional encyclopedia. The advanced search options that will be available at the end of Implementation Phase 1 are the following:

• Search on entry title in four languages
• Text search on the fact-files (brief identifications)
• Full text search
• Multiple Keyword search
• Metadata search (author, subject, period, material)
• Map search
• Test phase for spatial interactive searches (linking text entries to 3D models)
• Test phase for links between articles and original data (excavation records)

In Implementation Phase 1 map searches are performed through clickable maps that can zoom in on specific regions or sites. These provide links to articles in the encyclopedia on specific regions, sites, or monuments. In addition, interactive plans and models will be part of several entries on specific monuments and archaeological sites.

In future phases these search options will be expanded with:

• Related topic search
• Image database search
• Weighted keyword search / text analysis
• Data mining
• Maps based on Geographical Information Systems (GIS)
• Real time Virtual Reality models

One approach that we will explore as a way of incorporating innovative ways of navigating the encyclopedia is to experiment with data mining and visualization tools such as T2K (Text to Knowledge), Info Navigator , a forthcoming functionality of the Greenstone Digital Library, or topic maps such as Omnigator. We will explore other options such as Oracle's Intermedia, as well as 3D schematic renderings. This last option will allow users to search without needing to be familiar with specialized vocabulary and will likely become a useful classroom tool. The UEE will be flexible in its approach, and will keep abreast of the rapid developments in the field of Digital Humanities. The options listed here are likely to be only some of those available in the future.

The power of digital information, textual and pictorial, lies in the superior search and retrieval capabilities of digital tools for access and analysis. This not only provides the user with access to very specific content, but the cutting edge search capabilities that are being developed for the UEE will also generate new knowledge and new research paths. On the other hand, the digital encyclopedia still offers old fashioned browsing, similar to a printed encyclopedia, where interesting entries are found serendipitously, on the opposite page or a few pages away, of the actual subject under study. Added features will be the 'random browse mode' where a random selection of entries appear in a side bar, as well as a 'related browse mode' where the side bar shows related subjects, determined through the hierarchical structure that underlies the selection of entries. Unobtrusively highlighting subjects in the text is a convenient way to provide access to related entries.

The process of building an XML (Extensible Markup Language) Schema for the encyclopedia will be started at an early stage so that the articles can assume a consistent data model within which we can reference material that is external to the text - images, maps, references to other sites, bibliographic resources, and possibly dictionary resources within the Berlin Altägyptisches Wörterbuch and the METEOR project at the University of Chicago Oriental Institute.

XML will not be regarded as a standard in itself, but rather as a low-level markup language that can evolve to support the complexities of the project and guarantee that the content will always be re-usable in different contexts. It will be possible, for instance, to represent the encyclopedia as a METS object by using the external Dublin Core (DC) metadata and the Digital Library structural principles. We will, as we develop our schema, actively seek out other people developing large reference works, and seek advice from others working in the field of archeology to determine what they see as essential elements in an encyclopedia schema. Creation of a re-usable XML Schema for other humanities encyclopedias will be an important goal of the project.