This open source project is dedicated to making persistent memory programming easier for application developers. Most of the activity is focused on the Persistent Memory Development Kit, which builds on the programming model for persistent memory recommended by the SNIA NVM Programming Technical Workgroup.
What is persistent memory? See the full definition used by this project on the Glossary page. In short, it is a tier between memory and storage, with attributes of both: it is byte-addressable like memory, and persistent like storage.