Folk high schools (also adult education center, Danish: folkehøjskole; Dutch: volkshogeschool; Finnish: kansanopisto and työväenopisto or kansalaisopisto; German: Volkshochschule and (a few) Heimvolkshochschule; Bokmål: folkehøgskole, Nynorsk: folkehøgskule; Spanish: Universidad popular; Swedish: folkhögskola; Polish: Uniwersytet ludowy; Hungarian: népfőiskola) are institutions for adult education that generally do not grant academic degrees, though certain courses might exist leading to that goal. They are most commonly found in Nordic countries and in Germany, Switzerland and Austria. The concept originally came from the Danish writer, poet, philosopher, and pastor N. F. S. Grundtvig (1783–1872). Grundtvig was inspired by the Marquis de Condorcet's Report on the General Organization of Public Instruction which was written in 1792 during the French Revolution. The revolution had a direct influence on popular education in France. In the United States, a Danish folk school, called Danebod, was founded in Tyler, Minnesota.
Despite similar names and somewhat similar goals, the institutions in Germany and Sweden are quite different from those in Denmark and Norway. Folk high schools in Germany and Sweden are in fact much closer to the institutions known as folkeuniversitet in Norway and Denmark, which provide adult education. However, unlike the folkeuniversitet folk high schools in Sweden are not connected with a regular university. The Finnish adult education centers called työväenopisto and kansalaisopisto (Swedish: arbetarinstitut, literally 'workers' institute') are also part of the adult education tradition.
Other countries have also been inspired by Grundtvig's concept of popular education. In Nigeria, the United States, and India, a few schools have been built upon Grundtvig's principles for education.