This document describes 5 types of clouds: cirrostratus, altostratus, cumulus, stratocumulus, and cumulonimbus. Cirrostratus clouds appear as thin, wispy veils that can cause halos, while altostratus clouds form dense, even gray layers that allow limited sunlight. Cumulus clouds have flat bases and develop vertically into various shapes, and stratocumulus clouds appear as gray plates or banks. Cumulonimbus clouds are large, heavy rain clouds that develop from the lower levels up into the higher atmosphere.