1. A method of classifying web visitor sessions based on clickstreams, the method comprising: utilizing a visitor session classification system to: organize, utilizing a webpage categorization component of the visitor session classification system, web pages of a single website into web page categories; divide, utilizing a visitor session determination component, clickstreams of users visiting the website into visitor sessions; generate a matrix of weights corresponding to the web page categories relative to web page interactions to provide weightings for the web page categories, wherein each weight is applied based on a type of web page interaction, the matrix including a first weight for a first web page category relative to a first type of web page interaction; determine, by at least one processor of a machine running an intersession distance component, an extent of similarity between a first visitor session of a first user and a second visitor session of a second user by comparing a first set of web page interactions, including the first type of web page interaction, by the first user corresponding with the first web page category to a second set of web page interactions by the second user corresponding with the first web page category, wherein the extent of similarity is determined based at least in part on applying the first weight to the first web page category relative to the first type of web page interaction; classify, utilizing a visitor session classification component, the second visitor session into one of a target group or a non-target group based on the extent of similarity between the first visitor session and the second visitor session where the first visitor session is identified as corresponding to the target group based on an interaction with the website by the first user; and directing targeted information related to the website to the second user when the second visitor session is classified into the target group based on the extent of similarity between the first visitor session and the second visitor session.