Suppose each and every circle is a website, and an arrow is a link from one
website to another website, such that a user can click on a link within, say,
website F to go to website B, but not vice versa site. Search engines begin
by assuming that each website has an equal chance of being chosen by a
user depend. Next, crawlers examine which websites link to which other websites
and guess that websites with more incoming links contain valuable
information that users need.