Spring is one of the four seasons that comes after winter and before summer. Spring is characterized by a gradual increase in temperature, an increase in daylight and the appearance of the first green leaves on trees and shrubs. In spring, snow melts, which leads to an increase in the water level in rivers and lakes. At this time of the year, active vegetation growth begins, the first flowers appear and birds return from warm countries. Spring is also associated with renewal and rebirth, so this time of year is often associated with the start of new projects and plans.