Plutonic - in the crust, coarser grained usually. Volcanic - on the surface, usually finer grained Classification of igneous rocks based on texture and composition. Divisions based on size and relationship to surrounding country rock. Batholiths and stocks may be in part formed by metasomatism - contacts are sometimes sharp and igneous, and other times gradational.
Xenoliths are chunks of country rock in the igneous body, sometimes produced by magmatic stoping.