The MetaLinks Hyperbook Tool:
An Introduction/Overview

Tom Murray,

[document version: 2/10/04]

[Note: this is a "promotional" style overview of the MetaLinks project, listing its benefits and innovative aspects. For documents with a research perspective and references to related literature, see papers at This is a simple text document, these other papers have screen shots and graphic illustrations.]

MetaLinks is both a computer program and a design framework for electronic text books. That is, it is a new way to conceptualize books and a set of tools that make it easy to produce and maintain innovative interactive texts in a cost effective way. The software (a reaserch prototype) includes both authoring and reading modes and hyperbooks authored with MetaLinks can be read on an internet browser. It supports both focussed and exploratory learning in richly interconnected material.

MetaLinks hyperbooks are adaptive interactive hypermedia texts. The software accesses a database to create each hyperbook page when the reader navigates to it. Users/readers log in and the system keeps a record of their activities as they use the book, which uses this information to customize each page to the needs of the reader and situation. The innovations and advantages of MetaLinks fall into these categories, each of which is described below: supporting active reading, multi-level books, multi-theme books, deep content representation , avoiding hypermedia side effects, evolving content, and student modeling. MetaLinks achieves these benefits through a number of novel features, including "horizontal flow", "custom depth control," "narrative smoothing," "thematic links," and "schema support," described elsewhere. The software was developed to incorporate research findings from cognitive science, educational theories, and learning theories into a framework for digital texts. For further descriptions of the system, the design philosophy, comparisons between MetaLinks hyperbooks and other text technologies, and published research papers, see Before describing the benefits of the system below we should emphasize that the system has been shown to be highly usable. Seamless integration of several features allows all of the following benefits to be had almost "covertly", without subjecting the user to an overly complex interface.

Note: three versions of MetaLinks. In the following description we will refer to three versions of MetaLinks, which has been developed over 10 years by Dr. Tom Murray. Version I was developed at the University of Massachusetts with NSF and ONR grant funding (with the help of a team of programmers). It underwent several round of evaluation and there are numerous research publications describing this work. Hyperbooks authored using this version must be read via an internet browser. It has the limitation that, being completed several years ago, it does not run on current internet browsers (it runs on Netscape 4.6 but not higher versions). MetaLinks Version I.2 is MetaLinks Version I with the addition of a student modeling component. This component was fully developed but never tested. MetaLinks II is being developed by Dr. Murray without external funding. It adds several new hyperbook features. Hyperbooks authored in MetaLinks II can be read in stand-alone mode (i.e. without an internet browser). Note that MetaLinks is still a research or proof-of-content project. We do not have a bug-proof off-the-shelf commercial quality version available.

Supporting active reading. "Active reading" is a term used to emphasize the dynamic, opportunistic processes used by experts and motivated readers. It refers to a set of high level reading, searching, problem solving, and metacognitive skills that readers use as they use texts to proactively construct new knowledge. Active reading skills include skimming, scanning, reviewing, summarizing, planning, evaluating, deepening, exploring, etc. Though active reading skills are important because they lead to more efficient and effective comprehension and information finding, these skills are not very advanced in many students (and adults), and it is important to support, scaffold, and teach these skills. MetaLinks hyperbooks directly support a large number of active reading skills.

Multi-level books. MetaLinks has several features that allow users with diverse levels of expertise in a topic to use the same book. Through the custom-depth feature readers can easily and continuously adjust the depth or complexity of their reading path. The text "makes sense" to both novice and expert users. Other features make it easy for novice readers to obtain background and prerequisite information on any topic.

Multi-theme books. MetaLinks supports readers of diverse backgrounds, goals, and styles , and allows authors to create one on-line book that serves a range of different uses that would normally require several books. The thematic links feature allows authors to create a single book that can be read from multiple thematic perspectives or goals (for example theoretical, practical, and historical treatments of the same material). A single book works well in reference mode, narrative learning mode, and exploratory mode. While supporting users who wish to efficiently read about a particular topic, MetaLinks also supports reading that is inquiry-based or divergent (discovery, or curiosity-driven). This is particularly appropriate for open-ended questions and/or learning in ill-structured domains in which the richness of the content suggests multiple themes, perspectives, or learning paths.

Deep content representation. (This feature is most developed in MetaLinks II). A text contains important information implicitly in its very structure. In traditional books the author's interpretation of the relationships among topics, and the importance or relevance of topics are communicated through the structure of the Table of Contents, pointers such as "see Section 3"", and in how material is presented, e.g. in a side bar or foot note. MetaLinks allows authors to directly incorporate much more of the "deep structure" of their expertise than they can with paper texts or even with traditional hypermedia. "Thematic links" and "content schema" allow authors to create texts in which the conceptual structure of the content is accessible, the interrelations among concepts is evident, and any repeating or overarching issues, questions, or conceptual schema is visually evident. Structural or thematic relationships that remain implicit in traditional texts can be made explicit in MetaLinks hyperbooks. It supports the construction and conceptualization of content through four esssential "epistemic forms:" narrative, network, schema, and hierarchy.

Avoiding hypermedia "side effects." The distinguishing characteristic of hypermedia, i.e. the ability to navigate (or "jump") easily from one location to another, in addition to being responsible for its benefits, leads unavoidably to a set of problematic "side effects": disorientation, poor narrative flow, and poor conceptual flow, cognitive overload. MetaLinks includes many features that ameliorate these problems . For example, "narrative smoothing" allows for a smoother narrative experience even as users jump around in the hyperbook.

Evolving content. The content data-base of MetaLinks hyperbooks allows for easy modification, updating, and extension of hyperbooks. Version II also has the following features: a version history of each content page, and student annotations of hyperbook pages.

Student Modeling. (This feature is in MetaLinks I.2, and is partially implemented in MetaLinks II). MetaLinks records all student navigational events and feature uses. If the system is sent data indicating which topics have been mastered, the system can dynamically adapt the hyperbook to each student's mastery profile. This allows the system to warn users if they navigate to an earea for which they do not have the prerequisite knowledge. Links to pages to be marked according to whether they are "ready to be learned."