Other sites are more specific, based on the type of members, interests, location, or relationship desired.
A 2005 study of data collected by the Pew Internet & American Life Project found that individuals are more likely to use an online dating service if they use the internet for a greater amount of tasks and less likely to use such a service if they are trusting of others.
In Germany government financed NGOs like "Verbraucherschutzzentrale" sometimes help to sue online dating sites.
This problem is referred to as "catfishing" in pop-culture and has been made famous by a popular MTV program called "Catfish the TV show".
Some sites provide free registration, but may offer services which require a monthly fee.