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LIST OF FIGURES

spread to the general population. Originally, web pages were only served from

dedicated machines and system administrators were loathe to allow any but the

most trusted of their colleagues to deploy interactive web pages. There are good

reasons for this. A poorly written interactive web page can be a major security

risk. It can also devour system resources and greatly slow down, if not crash, a

server. In the past few years this has become less of a problem as most personal

computers now come with preinstalled web servers; thereby democratizing the

process for all those who have an internet connection.

The more important impediment to the spread of interactive web pages

among general users is that the langauges for developing such pages have just

been too difficult for novices to learn. Originally these pages were written

in primarily in PERL, an interesting but rather bizarre language favored by

hackers both for its power and for its mystique! More recently, Java has become

a popular language for writing these pages, but this still requires authors to

have at least one semester's worth of programming experience before they can

even start to build interactive web pages.

Goals of this book

In this book, we return to the original ideals of the World Wide Web and present

a simple language, Scheme, for developing interactive web pages and other web

programs. Scheme is similar to HTML in that it is easy for non experts to learn

the basic language and to build build fairly sophisticated interactive web pages.

Scheme is a dialect of Lisp (a language which was first developed in 1957 at the

dawn of the computer era).

We begin with an introduction to HTML and CSS for developing static web

pages.

Next we give an introduction to writing Scheme servlets, the most basic form

of interactive web page. These pages are written in a mixture of Scheme and

HTML.

We then introduce the JLIB windowing library and show how to write and

deploy programs that use Graphical User Interfaces. These programs are en 

tirely written in Scheme.

In the second part of the text we move on to more sophisticated topics such

as developing web programs that access databases and writing programs that

involve communication among multiple users.

Hardware and Software Requirements

The software that is used in this text is all free and open source. It can be

easily downloaded and installed on almost all platforms (Windows, Mac, Linux,

Unix). If this text is being used in a course, we also provide instructions for

setting up a central server which removes the requirement for all students to