Snow is a type of weather. When the air outside is cold enough, snow will fall from the sky. Snow is made from tiny pieces of ice that form clouds in the sky. The air cools the ice crystals so much that they make tiny snowflakes that fall to the ground. It can be very cold and slippery outside when there is snow on the ground. People can go sledding and make snowmen, snow angels and have snowball fights when it snows.