Developed and advanced (openly and collaboratively) by the non-profit OPeNDAP, Inc.,[2] DAP is intended to enable remote, selective data-retrieval as an easily invoked Web service.
OPeNDAP servers offer various types of responses, depending on the specific form of the client's request, including XML, JSON, HTML and ASCII.
In response to requests for content, OPeNDAP servers can respond with multi-part mime documents that include a binary portion with NetCDF or DAP-native encoding.
OPeNDAP's software for building DAP servers (on top of Apache) is dubbed Hyrax and includes adapters that facilitate serving a wide variety of source data.
DAP servers most frequently enable (remote) access to (large) HDF or NetCDF files, but the source data can exist in databases or other formats, including user-defined ones.