Open Standards Metadata & Interoperability –
OAI Protocol for Metadata Harvesting (OAI-PMH) OAI-PMH is a lightweight harvesting protocol for sharing metadata between services.
A protocol is a set of rules defining communication between systems. FTP (File Transfer Protocol) and HTTP (Hypertext Transport Protocol) are examples of other protocols used for communication between systems across the Internet.
the gathering together of metadata from a number of distributed repositories into a combined data store.
allows for useful communications and collaboration between information systems.