A microbiological culture is a way to determine the cause of infectious disease by letting the agent multiply (reproduce) in predetermined media. For example, a throat culture is taken by scraping the lining of the tissue in the throat and blotting the sample into an (often agar) media to screen for various harmful microorganisms. More generally, the term culture is used informally to mean "selectively grow" a specific kind of microorganism in the lab. It is the foundational and basic diagnostic method of microbiology.