Whenever a visitor opens a MySpace profile, the tracker attempts to collect information about their identity, including the time of visit, their IP address and (sometimes) their MySpace username.
MySpace profile trackers report their information to a central Web site affiliated with the party providing the scripts. Most trackers use the HTTP protocol to transport data from MySpace to a database. The parties who create the scripts and maintain the databases are typically enentrepeneurs attempting to provide a (hopefully ethical) service to the MySpace community. Subscribers log into their services periodically to view traffic and visitors reports.
Because of technical limits imposed on MySpace.com, identifying visitors by username generally only works when visitors are all subscribers to the same tracker service. Additionally, most reputable MySpace profile trackers will not share the IP addresses of visitors to protect confidentiality.