The last decade has seen an explosion in the number of online dating sites around the world, and the number of people using them. According to some estimates , there are over 8, online dating sites worldwide, and over 2, in the US alone. These days, it is often the first option for someone looking for romance, not the last. The industry has completely transformed a fundamental ct of human communication, changing how we meet new people and go looking for partners. In the US, online dating is now the second most common way for heterosexual couples to meet behind introductions through friends. According to some estimates, over a third of marriages in the US are now from couples who first met online.