Such sites earn revenue from a mix of advertising and sale of additional options.

This model also allows users to switch between free and paying status at will, with sites accepting a variety of online currencies and payment options.

Online dating (or Internet dating) is a system that enables strangers to find and introduce themselves to new personal connections over the Internet, usually with the goal of developing personal, romantic, or sexual relationships.

An online dating service is a company that provides specific mechanisms (generally websites or applications) for online dating through the use of Internet-connected personal computers or mobile devices.

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.

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.

The 2016 Pew Research Center's survey reveals that the usage of online dating sites by American adults increased from 9% in 2013, to 12% in 2015.

Further, during this period, the usage among 18- to 24-year-olds tripled, while that among 55- to 65-year-olds doubled.

Most services offer digital messaging, while others provide additional services such as webcasts, online chat, telephone chat (VOIP), and message boards.