However, Sam Yagan describes dating sites as ideal advertising platforms because of the wealth of demographic data made available by users.

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.

Profiles created by real humans also have the potential to be problematic.

For example, online dating sites may expose more female members in particular to stalking, fraud, and sexual violence by online predators.

Niche sites cater to people with special interests, such as sports fans, racing and automotive fans, medical or other professionals, people with political or religious preferences (e.g., Hindu, Jewish, Christian, Muslim, etc.), people with medical conditions (e.g., HIV , obese), or those living in rural farm communities.

In 2008, a variation of the online dating model emerged in the form of introduction sites, where members have to search and contact other members, who introduce them to other members whom they deem compatible.

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.

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.