Online dating sites use market metaphors to match people.
Since 2003, several free dating sites, operating on ad based-revenue rather than monthly subscriptions, have appeared and become increasingly popular.
Several newer sites such as Ok are beginning to offer more full featured dating services for free, and are starting to compete with staples in the free dating site world such as
Users of an online dating service would usually provide personal information, to enable them to search the service provider's database for other individuals.
Members use criteria other members set, such as age range, gender and location.
Some sites provide free registration, but may offer services which require a monthly fee.
Other sites depend on advertising for their revenue.
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. By 2007, many prominent studies show that Baby Boomer interest in online dating have soared.
However, market share was increasingly growing by several large commercial services, including Personals. Some online dating websites provide webcam chats between members.
Such sites earn revenue from a mix of advertising and sale of additional options.
Online daters may have more liberal social attitudes compared to the general population in the United States.
Other sites are more specific, based on the type of members, interests, location, or relationship desired.