In a move which will have an impact on the privacy of Facebook users, the social network said in an earlier this month announcement that it is changing the way it determines which ads should be shown to the users of its site.

The alteration announced by Facebook underscores a change in the company's data collection practices; and is the latest attempt by the company to push the boundaries of users' privacy concerns.

While Facebook ad choices in the past were largely based on what users were doing on the social networking site - that is, which pages they had liked, and which links they had clicked on -, the change announced by the company implies that Facebook will not only use the mentioned data, but will also take into account the things users do online or on their smartphones outside of the Facebook website and apps.

In other words, the changed data collection practice by Facebook means that if the company finds users visiting an adult-themed site, or shop for laxatives at an online drugstore or use a fitness app for tracking their workouts, it will serve up ads to users on the basis of that information.

About the change in Facebook's data collection practices, Jeff Chester - executive director ofconsumer advocacy group called the Center for Digital Democracy - said: "Facebook is going to use multiple ways to track their users and sell them to their advertisers."