Introduction sites differ from the traditional online dating model, and attracted a large number of users and significant investor interest.
Profiles created by real humans also have the potential to be problematic.
For example, online dating sites may expose more female members in particular to stalking, fraud, and sexual violence by online predators.
At the end of November 2004, there were 844 lifestyle and dating sites, a 38% increase since the start of the year, according to Hitwise Inc.
The stigma associated with online dating dropped over the years and people view online dating more positively.
While some sites conduct background checks on members, many do not, resulting in some uncertainty around members' identities.