A new Google service has raised privacy concerns, with the Internet giant theoretically able to collect information on users' surfing habits. 

Web History is a new free service that allows users to look back at and even search sites they have browsed previously.
The idea is to let users personalise their Web experience as well as to deliver targeted search results.
However, concerns have been raised that it also allows Google to collect information on users' surfing habits.
The very fact that Google is able to deliver the service means its has the ability to track and store users' activities and link them back to individual users.
To use Web History, users must have a free account and the Google Toolbar installed.