Both OkCupid and Hinge are online dating sites, some might say sophisticated ones. OkCupid for example, won the Malcolm Baldrige National Quality Award for Technology & Productivity. So, both are pretty well known and respected.
Both sites are relatively easy to use, create an account in a few minutes and start searching for potential partners. BUT, not just that. They are also very simple to use and provide a good user experience. They put a lot of themselves into developing an easy to use interface that helps their members to narrow their search for a partner.
Mentioned above, both services are very user-friendly and provide a good experience for their members in every respect. I will now attempt to provide you with some value-added input to help you decide between the two.