By Anya Khait
In their annual review of the World Wide Web, researchers at OCLC have determined that the Web now contains about 7 million unique sites, the public websites that offer content that
is freely accessible by the general public-constitutes about 40% of the total Web, and the Web continues to expand at a rapid pace, but its rate of growth is diminishing over time. According to the
group's latest estimates, there were 7.1 million unique web sites, a 50% increase over the previous year's total of 4.7 million. Although the number of websites has nearly tripled in size in the last
two years, year-to-year growth rates are declining, falling from almost 80% between 1998 and 1999, to only about 50% between 1999 and 2000. Public web sites constitute 41% of the Web, or about 2.9
million sites. Private sites - whose content is subject to explicit access restrictions (e.g., Internet Protocol filters or password authentication), or is not intended for public use (e.g., web
interfaces to privately owned hardware devices such as printers or routers) - comprise 21% of the Web, or 1.5 million sites. The remaining 2.7 million sites - or about 38% of the Web - are provisional
sites: their content is in an unfinished or transitory state (e.g., server default pages or "Site under construction" notices). Adult sites - those offering sexually explicit content - now
constitute about 2% of the public Web, or 70,000 sites. The proportion of the public Web occupied by adult sites has remained unchanged since 1998. "The Web continues to grow at a substantial rate,"
said Ed O'Neill, manager of the OCLC Web Characterization Project. "But a comparison of the year-to-year growth rates suggests that the Web's expansion is slowing. This trend is even more pronounced
in the public Web, which grew by about 80% between 1997 and 1998 but only by about a third between 1999 and 2000. Even in absolute terms, growth seems to be slowing: the public Web increased by
713,000 sites in the past year, compared to 772,000 sites between 1998 and 1999." Brian Lavoie, a research scientist working on the Web Characterization Project, notes the increasing incidence of
non-public web content. "For most people, the Web is the public Web-that's where most web browsing takes place. But there's a lot of content out there that you would probably never encounter in the
course of casual browsing; in other words, the private and provisional sites. Private sites in particular have exhibited steady growth relative to public sites in the past few years, accounting for
about 12% of the Web two years ago, compared to over 20% today."