The Off-Facebook Activity tracker sends itemized lists the websites, applications that the user has visited.
Facebook's data policy says they may also use the information when you visit a site with social plugins to help us show more interesting and useful advertisements. The information they collect depends on how you use their products. Also, Facebook uses these services to make their content and ads more engaging and relevant. The Off-Facebook Activity tracker shows what information is tracked from its use as it gives an itemized list of the websites, applications that the user has visited.