Just a new HTTP interface for Hadoop file system. The main differences between HttpFS and WebHDFS are that this one is created by Cloudera, not Hortonworks (on top of their previos Hoop library) and:
HttpFs is a proxy so, unlike WebHDFS, it does not require clients be able to access every machine in the cluster. This allows clients to to access a cluster that is behind a firewall via the WebHDFS REST API.
Question is: if they are API compatible and both open source, why not unifying them?
Original title and link: HttpFS: Another Hadoop File System Over HTTP ( ©myNoSQL)