A Petri dish is a shallow, cylindrical laboratory glassware used for culturing microorganisms, cells, and tissues. It features a flat, transparent surface with a fitted lid, allowing for the containment and observation of biological samples. Typically made from borosilicate glass or polystyrene, petri dishes are essential for conducting experiments in microbiology, where they provide a controlled environment for growing and analyzing bacterial, fungal, and other microbial cultures.