Wind is a large amount of airflow caused by the rotation of the earth and also because of differences in air pressure around it. The wind moves from high-pressure air to low-pressure air.
When heated, air expands. The expanding air becomes lighter so it rises. When this happens, the air pressure drops because the air is reduced. The cold air around it flowed into the low pressure place. The air shrank into more weight and descended to the ground. On the ground the air gets hot again and rises again. The flow of hot air and the decline of cold air is called convection.