Niche sites cater to people with special interests, such as sports fans, racing and automotive fans, medical or other professionals, people with political or religious preferences (e.g., Hindu, Jewish, Christian, Muslim, etc.), people with medical conditions (e.g., HIV , obese), or those living in rural farm communities.In 2008, a variation of the online dating model emerged in the form of introduction sites, attracting a large number of users and significant investor interest.
A great diversity of online dating services currently exists.
Some have a broad membership base of diverse users looking for many different types of relationships.
Some sites are completely free and depend on advertising for revenue.
Others utilize the freemium revenue model, offering free registration and use, with optional, paid, premium services.
Since advertising revenues are modest compared to membership fees, free dating sites require a large number of page views to achieve profitability.
However, Sam Yagan describes dating sites as ideal advertising platforms because of the wealth of demographic data made available by users.
That is, online dating sites use the conceptual framework of a "marketplace metaphor" to help people find potential matches, with layouts and functionalities that make it easy to quickly browse and select profiles in a manner similar to how one might browse an online store.
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.
Because online dating takes place in virtual space, it is possible for profile information to be misrepresented or falsified.
While some sites conduct background checks on members, many do not, resulting in some uncertainty around members' identities.
Other sites target highly specific demographics based on features like shared interests, location, religion, or relationship type.