  We present a theory for the growth dynamics of the World Wide Web that takes
into account the wide range of stochastic growth rates in the number of pages
per site, as well as the fact that new sites are created at different times.
This leads to the prediction of a universal power law in the distribution of
the number of pages per site which we confirm experimentally by analyzing data
from large crawls made by the search engines Alexa and Infoseek. The existence
of this power law not only implies the lack of any length scale for the Web,
but also allows one to determine the expected number of sites of any given size
without having to exhaustively crawl the Web.
