Agarwood, also known as oud or agar, is a highly sought-after aromatic resinous wood derived from the heartwood of Aquilaria and Gyrinops trees. These trees produce agarwood in response to a fungal infection, which stimulates the tree to produce a dark, fragrant resin. This resin is highly prized for its distinctive aroma and is used in various forms such as chips, incense, and attars.