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.
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.
While some sites conduct background checks on members, many do not, resulting in some uncertainty around members' identities.
For instance, some profiles may not represent real humans but rather "bait profiles" placed online by site owners to attract new paying members, or "spam profiles" created by advertisers to market services and products.
Online dating services allow users to become "members" by creating a profile and uploading personal information including (but not limited to) age, gender, sexual orientation, location, and appearance.
Over 50% of research participants in a 2011 study did not view online dating as a dangerous activity, whereas 43% thought that online dating involved risk.
Because online dating takes place in virtual space, it is possible for profile information to be misrepresented or falsified.
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.
A great diversity of online dating services currently exists.