The Open Textbook Library was started so that faculty could find open textbooks in one place. More technically, the Open Textbook Library is a comprehensive referatory that points to open textbooks by a variety of authors and publishers. OTL defines an open textbook as one that has an open license that makes it free for anyone to use and change. It can be print or digital.
CORA is intended to be a collaborative space for adapting and experimenting with research assignments and sharing the success or lessons learned so that others may benefit. The site contains multiple, reliable and reproducible research assignments that do not live as isolated entities.