Most speed dating events match people at random, and participants will meet different "types" that they might not normally talk to in a club. On the other hand, the random matching precludes the various cues, such as eye contact, that people use in bars to preselect each other before chatting them up.
Many sites are broad-based, with members from a variety of backgrounds looking for different types of relationships. Other sites are more specific, based on the type of members, interests, location, or relationship desired.
