More traditional sites may offer anything from a simple search to a highly specific advanced search.
Some more seriously minded sites request that members fill out elaborate compatibility questionnaires.
Launched in 2004, OKCupid works with many populations of people.
Focusing on a narrow pool of candidates, these online dating sites help match people up with someone of a similar religion, profession, or sexual orientation.
Examples within this category include Jdate for Jewish singles, Geek2Geek and Farmersonly for farmers and the people who want to meet them.
Check to see what safeguards are put in place by the site, and which ones you can enable to limit those who sees your profile.
Most dating sites have become extremely good about policing their members for negative or unsafe behavior.