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

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.

The stigma associated with online dating dropped over the years and people view online dating more positively.

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.

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.

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.

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

Members can constrain their interactions to the online space, or they can arrange a date to meet in person.

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 number of tasks, and less likely to use such a service if they are trusting of others.