An academic year or school year is a period of time which schools, colleges and universities use to measure a quantity of study. School holiday School holidays (also referred to as vacations, breaks, and recess) are the periods during which schools are closed or no classes or other mandatory activities are held. The dates and periods of school holidays vary considerably throughout the world, and there is usually some variation even within the same jurisdiction. Governments often legislate on the total number of school days for state schools. The holidays given below apply to primary and secondary education. Teaching sessions (terms or semesters) in tertiary education are usually longer. Terminology Spring vacation In countries with a Christian religious tradition, the Easter holiday, which in the United States is sometimes known as spring break, is a holiday that takes place in the northern spring. The date varies mainly because Easter is a movable feast, but also by country and level of schooling. Summer vacation In the northern hemisphere, the longest break in the educational calendar is in the middle of the year, during the northern summer, and lasts up to 14 weeks. In Ireland, Italy, Latvia, Lithuania, and Russia, summer holidays are normally three months, compared to six to eight weeks in Britain, the Netherlands, and Germany. In the southern hemisphere, the longest break in the educational calendar is in the end-beginning of the year, during the southern summer, and lasts up to 14 weeks, from December 21 to March 20. Common practices and effects Summer holidays for most children are a time to relax, enjoy themselves, catch up on studies, or spend time with family or relatives. Many families travel together on school holidays. School holidays have many effects on a country, ranging from the price of travel and holiday accommodation, which increase as demand increases while children are off school, to a change in crime rate: Example UK crime rate monthly figures. Traffic congestion and heavy passenger loads on public transport on school run routes may be worse on school days during term time. The number of families taking holidays away from urban areas can reduce traffic and use of public transport in cities while loading long-distance highways and means of transport. In some countries, i.e. Netherlands, where many families travel to their holiday destinations, the start and end dates of school holidays in different regions are staggered to