While the database itself needs to be searchable we also want to make sure we aren't sharing information unnecessarily and/or without permission.
At time of writing there is no login required to browse the database.
To add to the database (either in terms of adding yourself or recommending others) you need to provide your email address so we know who is contributing content. That email address will never be made public.
However, if you add your email address to your profile then it will be public (somewhat obviously).