8.4 The Mysterious PageRank
You'll hear a lot of
people talk about Google's PageRank, bragging about
attaining the misty heights of rank seven or eight, talking in hushed
tones of sites that have achived nine or ten. PageRanks range from 0
(sites that haven't been ranked or have been
penalized) to 10 (reserved only for the most popular sites like
Yahoo! and Google itself). The only place where you can actually see
what PageRank a given URL has is from the Google Toolbar [Hack #24], though you can get some idea of popularity
from the Google Directory. Listings in the Google Directory contain a
green bar next to them that allow you to give a good idea of the
listing's popularity without having an exact number.
Google has never provided the entire formula for their PageRank, so
all you'll find in this book is conjecture. And it
wouldn't surprise me to learn that
it's changing all the time; as millions of people
try myriad things to make sure their pages rank better, Google has to
take these efforts into account and (sometimes) reacted against them.
Why is PageRank so important? Because Google uses that as one aspect
of determining how a given URL will rank among millions of possible
search results, but that's only one aspect. The
other aspects are determined via Google's ranking
algorithm.
|
