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.
Other sites target highly specific demographics based on features like shared interests, location, religion, or relationship type.
Online dating services also differ widely in their revenue streams.
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.
Most services also encourage members to add photos or videos to their profile.
Once a profile has been created, members can view the profiles of other members of the service, using the visible profile information to decide whether or not to initiate contact.
Still others rely solely on paid membership subscriptions.
Opinions and usage of online dating services also differ widely.
Introduction sites differ from the traditional online dating model, and attracted a large number of users and significant investor interest.
In Eastern Europe, popular sites offer full access to messaging and profiles, but provide additional services for pay, such as prioritizing profile position, removing advertisements, and giving paying users access to a more advanced search engine.
A great diversity of online dating services currently exists.