Under this metaphor, members of a given service can both "shop" for potential relationship partners and "sell" themselves in hopes of finding a successful match.
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.
In 2008, a variation of the online dating model emerged in the form of introduction sites, where members have to search and contact other members, who introduce them to other members whom they deem compatible.
Introduction sites differ from the traditional online dating model, and attracted a large number of users and significant investor interest.
Some have a broad membership base of diverse users looking for many different types of relationships.
Most services also encourage members to add photos or videos to their profile.Online dating services also differ widely in their revenue streams.Some sites are completely free and depend on advertising for revenue. One in two sexually active young people will get an STD by age 25, and most of them won’t even know it. For those that choose to have sex, practice safe sex. Abstinence is the best way to protect against STDs.