Here is search logs of 650,000 AOL users. It's very interesting to view search history of particular person and analyze his personality. Let's do it together! Read more about AOL search database scandal or view research papers on web searching.
one to one function
In mathematics, a bijection, or a bijective function is a function f from a set X to a set Y with the property that, for every y in Y, there is exactly one x in X such that f(x) = y.