SpringerLink (http://link.springer.com) is Springer’s main content platform, which provides access to 9 million research documents. SpringerLink aims to become the primary resource destination for all academic researchers and students.
Springer for R&D is essentially the same platform as SpringerLink with access to exactly the same content, but the layout and organisation has been optimized for corporate & health markets. Springer for R&D (http://rd.springer.com) aims to become the primary resource destination for all corporate and medical customers.
You can easily switch between the two platform formats at anytime by selecting the drop-down menu option in the top-right-hand side of the page: