Seasonal unemployment occurs when people are unemployed at certain times of the year, because they work in industries where they are not needed all year round. Agriculture is heavily dependent on seasons for activities like sowing, harvesting, etc. Many agricultural workers are employed only during peak seasons and remain unemployed or underemployed during the off-season. Cyclical unemployment is related to the overall business cycle, structural unemployment is due to a mismatch of skills or location, and frictional unemployment is short-term unemployment between jobs; while these can exist in agriculture, seasonal unemployment is a defining characteristic of employment patterns in this sector, especially in regions heavily reliant on rain-fed agriculture.