Cloud formations are visible masses of condensed water vapor floating in the atmosphere. They are classified into different types based on their appearance, altitude, and the processes that create them. Common types include cumulus, stratus, and cirrus clouds, each with distinct characteristics. Clouds form when warm, moist air rises and cools, causing water vapor to condense into tiny droplets or ice crystals. This process can occur due to various factors, such as weather fronts, topography, or convection. The resulting formations can indicate different weather patterns and play a crucial role in the Earth's climate system.