Caffe2 is an open-source deep learning framework, which is developed and maintained by Facebook, and is based on the Caffe framework.
Caffe2 is a deep learning framework, which is based on the caffe framework. It is developed and maintained by Facebook, and released under the Apache 2.0 license, on GitHub.
Caffe2 is an improved / redesigned version of Caffe. A presentation by Caffe2's lead developer Yangqing Jia, held at CVPR 2015, shows some of the consideration of the redesign.