A holodeck pattern buffer or "holobuffer" was a data storage system in which holographic programs were stored when they were not in use. Part of a ship's holodeck systems, it acted in a similar function to the transporter's pattern buffer.
In 2377, USS Voyager received a large transmission from Starfleet. Since the subspace transceiver was not designed to store holographic patterns, Harry Kim transferred the hologram to the holodeck's pattern buffer. (VOY: "Inside Man")