To allow you to express yourself beyond just the information collected during registration, we enable you to provide additional information, such as your first and last names, email address, social media account names, your birthday, a bio, favorite URLs, and instant messaging IDs. In addition, you may choose to include photos of yourself in your profile.

A username is sufficient to register to the service. But if you provide a Name and other information, they “must be accurate, complete, and current at all times. Failure to do so constitutes a breach of the Terms, which may result in immediate termination of your 500px account.”