Chimney caps are protective coverings installed on top of chimneys. They serve several purposes: keeping chimneys dry, preventing animals from nesting inside, and stopping drafts from allowing smoke and ash to enter the home. There are different types of chimney caps for various chimney styles, including integral damper mechanisms, draft increasing caps, standard caps, electric draft increasing caps, single flue caps, band-around brick caps, and top mount caps. Chimney caps help maintain proper chimney function and fireplace safety.