The World Wide Web has had over 5 years of intensive development, and
has expanded from a text-only technical documentation system to a mult
imedia information base distributed across the planet. Although its to
ol for structural definition, the Hypertext Markup Language (HTML), ha
s been under constant development throughout this period, most browser
s have been slow to take advantage of all the facilities it offers. At
a time when there is much debate over the public future of the Web, i
t is in danger of partial stagnation. Despite significant innovations
in some areas, the field is still open for software developers who are
capable of harvesting the benefits of SGML, the language in which HTM
L is written. This analysis of HTML Document Type Descriptions (DTDs)
reveals where some of the opportunities may lie.