Hypertextbooks and a Hypertextbook Authoring Environment 1

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1 Hypertextbooks and a Hypertextbook Authoring Environment 1 Rockford J. Ross Computer Science Department Montana State University Bozeman, MT, USA ross@cs.montana.edu ABSTRACT An ITiCSE 2006 working group explored the prospect of deploying educational visualizations (e.g., algorithm visualizations) in hypertextbooks [10]. In this paper we present our continuing work on a hypertextbook project that demonstrates the viability of many of the issues raised in that workshop. The project has two thrusts: (1) the authoring of hypertextbooks for specific academic subjects, and (2) the creation of an authoring environment for prospective hypertextbook authors. The status of both is discussed in detail. It is anticipated that the success of the project as well as access to the authoring environment will inspire the creation of more active-learning hypertextbooks covering many academic subjects. Categories and Subject Descriptors K.3.2 [Computers and Education]: Computer and Information Science Education Computer science education. General Terms Algorithms, Theory. Keywords Hypertextbooks, active learning, algorithm visualization, concept animation. 1. INTRODUCTION The term hypertextbook has been used to describe many different computer- or web-based learning systems. The concept, as presented here, was first published in [1, 2]. Hypertextbooks have since been the primary focus of the Webworks Laboratory in the Computer Science Department at Montana State University under the direction of the author. 1. This work is supported in part by the National Science Foundation, grant number 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. ITiCSE'08, June 30-July 2, 2008, Madrid, Spain. Copyright 2008 ACM /08/06...$5.00. In our view, a hypertextbook is a teaching and learning resource that is delivered via standard Web browsers, making use of all relevant Web technologies to provide students and instructors with a rich, active-learning environment. For client-side delivery, arbitrarily many high definition images (with zoom-in, zoom-out capabilities), slide shows with multiple sound tracks, and video clips with the usual complement of user-managed controls can be seamlessly embedded into a textual presentation that is variously directed towards different leaning levels and needs via hyperlinks. Most importantly, interactive Java visualization applets of key concepts can be integrated into the fabric of a hypertextbook, providing a unique educational environment for students and instructors alike. Algorithm visualizations, animations of basic concepts such as finite state automata, the instruction fetch and execute cycle of a processor, problem reductions, and so forth can be constructed so that students engage in active learning as they study these concepts, a feature that cannot be emulated in a traditional hardcopy textbook. The primary inspiration for hypertextbooks has come from the computer science education animation and visualization community. For many years, this community has been developing visualization systems for various concepts in computer science, most notably algorithms [6] and theory [7, 8], including this author s contributions [3]. As time progressed, however, an unexpected trend began to be observed: Even though a number of visualization systems were quite good eliciting enthusiastic responses when presented at computer science education conferences actual use of these systems was generally limited to the institutions at which they were created. Possible reasons for this phenomenon were reported in [3], in which it was suggested that overtaxed instructors likely had neither the time nor energy to prepare for using visualizations in their courses that might be relevant in just a few lectures. Such preparation often meant that instructors had to search for good visualizations download them possibly install them (and resolve local system incompatibilities) learn them teach students how to use them deal with inconsistencies in notation between the visualization system and the course textbook 133

2 assign and grade exercises involving the use of visualization systems And all of this effort was likely for just a few lectures on the subject being visualized. Given this observation, the concept of a teaching and learning resource based on web technologies that could serve as a replacement for a traditional hardcopy textbook evolved. The motivation was simple: if visualization systems could be incorporated seamlessly into the fabric of a hypertextbook, all of the issues described above that had previously stymied their use in the classroom would be solved. Subsequently, the hypertextbook concept was given a more thorough treatment in an ITiCSE workshop [10]. The project described here thus represents both the author s ongoing work and a concrete response to the findings and recommendations of that workshop. The project currently has two thrusts: the creation of a hypertextbook authoring environment, and the authoring of actual hypertextbooks for academic subjects. 2. HYPERTEXTBOOKS UNDER DEVELOPMENT Two hypertextbooks are under construction by the hypertextbook team Theory of Computing: The Hypertextbook, and Biofilms: the Hypertextbook. The latter is currently receiving the most attention, as it is the subject of an interdisciplinary grant from the National Science Foundation. Applying the hypertextbook concept initially devised for the hypertextbook on the theory of computing to the subject of biofilms 2 has been beneficial for a number of reasons: 1. It has provided a means for verifying that the hypertextbook concept works across disciplinary boundaries. 2. It enforces the use of web technologies that are easily used by computer novices. 3. It provides the project with feedback from instructors and students with a wide variety of backgrounds. These have been invaluable in structuring the hypertextbook infrastructure for general audiences. 2.1 General Hypertextbook Features It is difficult to convey the features of the hypertextbook in print. To experience them, the reader is encouraged to visit the website of Biofilms: The Hypertextbook, Version 2 [5]. This link showcases the format and features of the current hypertextbook infrastructure (for comparison with the prototype, referred to as Version 1, see [4]). As noted, the hypertextbook on biofilms is receiving the most attention at the moment as a result of a National Science Foundation grant that supports its development. Porting of Theory of Computing: The Hypertextbook to this new infrastructure is a straightforward process that will occur during the early months of the spring 2008 semester. For a review of the rough prototype, see [9]. 2 To see what biofilms are, follow the link to Biofilms: The Hypertextbook [5] and take a look at the introductory section. Some of the primary features of Version 2 of the hypertextbook infrastructure are: 1. A common page layout that keeps all navigation menus visible at all times, allowing only the content to be scrolled. 2. Automatic resizing of pages to fit the browser window so that no browser scrolling is necessary to view any of the page structure of the hypertextbook. 3. Common dropdown menus (that are always visible in the top pane of every page) that provide for easy navigation of the hypertextbook. 4. Common next and previous page links (that are always visible in the bottom pane of every page) that allow for direct accesses to pages that occur in sequence in the book. 5. Three distinct tracks through the material for novice, intermediate, and advanced students. 6. Standard formats for images, slideshows, and video clips (with audio and/or narration tracks) 7. Ready incorporation of active learning Java visualization applets. 8. Interactive self-test quizzes with feedback. 9. Cross browser viability the hypertextbooks work in all common browsers (with one exception regarding mathematical notation, discussed later). 10. Simple deployment users need only ensure that the Java runtime environment and Adobe Flash plugins are installed on their browsers (over 99% of all browsers in the world are reputed to have the Flash plugin already installed, and the Java runtime environment is also widely integrated into browsers). 2.2 Embedded Active-Learning Applets Specific to the Theory Hypertextbook Of special interest to computer science educators is the set of active learning applets included in the theory hypertextbook. These include models for viewing, constructing, and testing (with feedback): Finite state automata (including nondeterminism) Regular expressions Regular grammars The minimization of finite state automata (still under construction) The conversion of nondeterministic to deterministic finite state automata Pushdown automata Context free grammars All except the more recent models have been reported in [3]. 3. THE AUTHORING ENVIRONMENT In order to inspire others to author hypertextbooks on arbitrary subjects, the project team has created an environment that makes 134

3 the task easier. The environment is based on the web development system Adobe/Macromedia Dreamweaver. 3.1 The Dreamweaver Toolkit Prospective hypertextbook authors can be provided with the hypertextbook infrastructure in the form of a Dreamweaver site that includes: A standard file structure for hypertextbook content. A set of standard templates from which content pages can be constructed in uniform fashion (a Dreamweaver template allows new pages to be created based on the template, which itself contains all of the formatting and page layout code, resulting in pages that are consistent in appearance; furthermore, changes to a template propagate through all pages created from that template, allowing for single point changes to page design and layout). An extensive set of style sheets that provide a consistent style and visual appearance to the entire hypertextbook. Changes, ranging from minor tweaks to an entirely different look (e.g., to distinguish one hypertextbook from another), are possible through changes to the style sheets rather than the actual pages of the hypertextbook. A set of code snippets that allow a hypertextbook author to insert consistent container code for images, slide shows, video clips, and applets. A number of javascript functions that manage various aspects of the hypertextbook presentation. 3.2 A Navigator Generator The most onerous task involved in hypertextbook construction is the maintenance of consistent and accurate navigation hyperlinks. The problem is compounded because the natural process of constructing a hypertextbook includes the insertion, deletion, renaming, and reordering of chapter, section, and page content a process that wreaks havoc on hyperlinks. This issue has been resolved by the hypertextbook team through development of a Perl program that preprocesses the hypertextbook website prior to its publication to a server. The program scans the site, makes note of the location of all pages, constructs menus for chapters, sections, appendices, and help directories, as well as the individual pages that these directories contain. A second pass through the site then looks for special metadata comments in each page (propagated through all pages by the templates upon which these pages were built) that indicate which menus are to appear in that page. The proper HTML code for the menus is then deposited by the Perl program at that point. 3.3 Comments on Hypertextbook Authoring Authoring a traditional textbook is a rewarding, but arduous task. The same, and perhaps more, can be said about authoring a hypertextbook. A hypertextbook author must not only craft words, but also deal with the creation of digital images, digital movies, slide shows, and active learning applets. In addition, a hypertextbook author must be somewhat of a graphics designer, with an eye for aesthetics. In other words, the construction of a hypertextbook requires a number of skills that may not all be held by the author. A hypertextbook authoring environment, such as the one described here, makes these aspects of hypertextbook construction immensely easier. Furthermore, there are some distinct advantages to the authoring of a hypertextbook as opposed to a traditional hardcopy textbook. 1. A hypertextbook can be released in increments. A single chapter in a computer science theory hypertextbook on finite state automata is useful to students by itself, even if the eventual goal is a complete undergraduate hypertextbook on the theory of computing. 2. A hypertextbook is easily updatable at regular intervals (e.g., semester by semester). Simple typos can be fixed immediately. 3. The aids included in a hypertextbook can be extended at these same regular intervals; if additional interactive examples, quizzes, videos, and so forth are deemed helpful, these can be included with impunity over time. 4. Hypertextbook authoring is done in what is essentially an instant gratification WYSIWYG environment. Changes to the hypertextbook are immediately viewable in a browser. 4. EVALUATION The hypertextbooks of the project continuously undergo regular, in-class formal and informal evaluation by both students and instructors. The questions being investigated include those that determine the usability of the hypertextbook how well students learn with the hypertextbook how students feel about their experience with the hypertextbook compared to traditional textbooks whether there are any technical issues that impede the use of the hypertextbook how well the hypertextbook meets the needs of the instructors (who also serve as peer reviewers of hypertextbook content). The team collects all of the evaluation instruments for review by an educational evaluation expert. Initial evaluations continue to show the following. 1. Students enjoy using the hypertextbook more than a regular textbook. 2. Students really like the slide shows, video clips, interactive quizzes with feedback, and active learning models with feedback. They regularly request that more be included. 3. In nearly every tested group of students there are a few who have technical trouble with the hypertextbook, but the vast majority report no trouble. 4. Students learn at least as well by way of a hypertextbook as they would with traditional learning resources (verified by pre- and post-testing student knowledge). 5. Students generally seem more engaged with the subject matter when using a hypertextbook. 135

4 The intent of the team is to publish all of the formal and informal evaluation summaries on a project website for anyone to access. 5. COMPARISON WITH OTHER SYSTEMS Since the conception of the hypertextbook idea, a number of other web-based teaching and learning resources have emerged. These range from simple, static Portable Document Format (PDF) renditions of traditional hardcopy textbooks, to more sophisticated PDF documents (which now can contain various kinds of dynamic content), to Wikipedia, and so forth. It is the author s opinion that each of these resources plays a useful role in education. Yet there seems to be strong sentiment that carefully crafted, peer-reviewed, complete teaching and learning resources reminiscent of traditional textbooks are still important to education. Evidence of this latter observation can be found in Knol (a Google search on Knol leads to many descriptions of it), a system being promoted by Google as a counterpoint to the Wikipedia paradigm. In Knol, established experts are invited to produce content (i.e., a paper ) that remains tied to the author s name and thus carries the weight of authority and implied accuracy. Finally, the cohesive nature of a complete, integrated treatment of a subject in which terminology and notation remain consistent must surely be perceived as beneficial to learning. In short, every avenue that works to disseminate knowledge and engender learning is to be applauded. The hypertextbook is one of those avenues. 6. HURDLES Even just a year ago there were some tough hurdles to overcome in achieving one objective of the hypertextbook concept that it be universally accessible on virtually any web browser. These hurdles included the disparity among plugins and file formats required to run slide shows, video clips, and applets, as well as the capacity for browsers to display mathematical notation natively. At this juncture, applet execution seems to have stabilized quite nicely, and JPEG still images are displayable in all common media player plugins for browsers of which the author is aware. Finally, with the December, 2007, release of version 9 of Adobe s Flash player, virtually any browser can now display media clips in a standard file format (MPEG-4, H.264) through either the Flash plugin or Apple s QuickTime plugin (as well as other, less widely deployed media player plugins), allowing hypertextbook authors to fix on that single file format for videos. The only remaining hurdle is that of uniform browser rendering of mathematical notation in standard MathML form. The Mozillabased browsers have been able to render MathML natively for some time. The Internet Explorer and Safari browsers do not. For computer science students, the target audience for Theory of Computing: The Hypertextbook, this is not an issue. There is certainly no impediment to requiring that a computer science student install Firefox, for example, as the browser to use with the hypertextbook. Indeed, it seems that most computer science students have this browser already installed; it runs on Windows, Linux, and Mac OS platforms. For users who are not computer savvy, however, this remains an issue for hypertextbooks with extensive mathematical content. There are some workarounds, but in order for a hypertextbook to be successful, it should work with minimal or no browser tweaking on the part of the user. On the other hand, students of this generation are generally quite adept at dealing with software quirks. It remains to be seen whether requiring use of a browser like Firefox of the general student really is a problem or just an imaginary impediment. Finally, authoring a hypertextbook with mathematical content is still a convoluted process. The way this author does it is to produce necessary mathematics in Amaya, the web browser developed by the World Wide Web Consortium for testing purposes. It has a WYSIWYG environment for writing mathematics. Once created in Amaya, the MathML content is cut and pasted into the pages of the hypertextbook. Although not convenient, this process is not quite as bad as it seems, as much of the mathematics shows up repetitively in the text and can be created once and copied and pasted as often as necessary. 7. THE FUTURE 7.1 Extending the Hypertextbook Concept The hypertextbooks and the hypertextbook authoring environment described here are already proving their worth to students, instructors, and authors. They are, however, mere shadows of what they can become, even within the limits of current technology. In the context of a Web 2.0 client-server model, for example, a hypertextbook could become part of a complete course management system, as envisioned by the aforementioned ITiCSE working group on hypertextbooks. 7.2 Enhancing Hypertextbook Capabilities Other client-server technologies that enhance the effectiveness of the hypertextbook itself are within reach, including one currently being explored by a member of the hypertextbook team: just-intime glossary and index information that can be presented to a user when the mouse is clicked on a word or phrase in the hypertextbook. Retrieved information might include images, video clips, and other artifacts that explain the concept (similar systems already exist). 7.3 Reformulating the Authoring System The hypertextbook authoring environment could be reformulated as a standalone hypertextbook authoring system that is not tied to a particular web development environment. Features it might have include the dragging and dropping artifacts (such as video clips, audio clips, images, applets, and so forth) into a desired position on a page with underlying software that automatically reformats the artifacts into a standard file format and embeds them into code that can play in a standard media player plugin. 7.4 Supporting Hypertextbook Development National Science Foundation grant support provides a great opportunity to pursue a project like this. However, grants run out. The National Science Foundation explicitly requires that grantees identify ways to commercialize or otherwise ensure that the educational resources that result from such a grant remain viable long after expiration of the grant. The hypertextbook team continues to explore ways to accomplish this. There are methods, for example, to host the system on servers provided by 136

5 companies, such as Amazon.com, which will also provide the necessary e-commerce infrastructure for sales of a hypertextbook. In all scenarios considered by the hypertextbook team it appears that the cost of a hypertextbook would be an order of magnitude less than traditional hardcopy textbooks when served in this fashion. 7.5 Intellectual Property and Patents There is one murky and somewhat distasteful aspect of web development projects that needs to be mentioned in passing here: intellectual property issues. This has become a thorny issue because some companies are either being awarded patents on software ideas without due effort to uncover prior art, or are claiming outright that their patents cover ideas that have long been considered part of the public domain. International law regarding patents is also not at all standard or clear. One only hopes that educational initiatives, such as the hypertextbook, remain unscathed by these problems. 8. SUMMARY We have described the current state of our hypertextbook project. The hypertextbooks under development are usable, often updated and extended with new content, regularly evaluated, and modified in response to feedback. Their enthusiastic reception by instructors and students represents an affirmative answer to the question of their viability as an educational resource. The project also serves as a working prototype of the objectives of the ITiCSE 2006 working group on hypertextbooks. In addition to functional hypertextbooks, the project described in this paper has also produced an authoring environment that can be used by other aspiring hypertextbook authors. The authoring environment affords authors the luxury of focusing on content rather than on the details of website development. This environment is available to anyone who would like to use it. It is hoped that it will inspire the creation of other active-learning hypertextbooks for computer science and other disciplines. REFERENCES [1] Boroni, Christopher, Goosey, Frances, Grinder, Michael, Lambert, Jessica, and Ross, Rockford. Tying it All Together: Creating Self-Contained, Animated Interactive, Web-Based Resources. In Thirtieth SIGCSE Technical Symposium on Computer Science Education (SIGCSE Bulletin), volume 31, number 1, pages 7 11, March [2] Boroni, Christopher, Goosey, Frances, Grinder, Michael, and Ross, Rockford. Engaging Students with Active Learning Resources: Hypertextbooks for the Web. SIGCSE Bulletin, volume 32, number 1, pages 65 69, March [3] Cogliati, Joshua J., Goosey, Frances W., Grinder, Michael T., Pascoe, Bradley A., and Ross, Rockford J. Realizing the Promise of Visualization in the Theory of Computing. Journal of Educational Resources in Computing, Volume 5, Issue 2, June [4] Cunningham, Alfred, and Ross, Rockford J. Biofilms: The Hypertextbook (Version 1). biofilmbook. [5] Cunningham, Alfred, and Ross, Rockford J. Biofilms: The Hypertextbook (Version 2). ross/projects/biofilmbook [6] Naps, Thomas, and Rößling, Guido. JHAVE More Visualizers (and Visualizations) Needed. Proceedings of the Fourth Visualization Workshop. June 2006, Florence, Italy. [7] Rodger, Susan. Java Formal Language Automata Package (JFLAP). February [8] Rodger, Susan, and Finley. Thomas W. JFLAP: An Interactive Formal Languages and Automata Package. Jones and Bartlett Publishers, [9] Ross, Rockford J. Theory of Computing: The Hypertextbook (rough prototype) [10] Rößling, Guido, et al. Merging Interactive Visualizations with Hypertextbooks and Course Management. ACM SIGCSE Bulletin, Working group reports on ITiCSE on Innovation and Technology in Computer Science Education, Volume 38, Issue 4, June