e Harmony is another massive player, with 3 million users signed up.
Plenty of Fish is available to those who live in the United States, Canada, UK, Australia, France, Germany, Ireland, New Zealand and Spain.
Plenty of Fish offers free and paid upgrade memberships.
Like most dating sites these days Plenty of Fish is a mix between a social networking site and a dating site.
You have the ability to engage in web chats, communities and meet singles in your local area.
This week marks the biggest online dating week of the year (combined with the biggest divorce week of the year).