Endospore staining is a specialized technique used in microbiology to identify and visualize endospores, which are resistant structures formed by certain bacteria to survive harsh conditions. The process typically involves applying a primary stain, such as malachite green, followed by heat to help the dye penetrate the tough outer layer of the endospore. After rinsing, a counterstain, like safranin, is applied to color the vegetative cells. This staining method allows scientists to differentiate between endospores and vegetative cells under a microscope. Endospores appear green, while the surrounding cells take on a pink or red hue. This contrast aids in studying bacteria like Bacillus and Clostridium, which are known for their endospore formation.