A secondary school is both an organization that provides secondary education and the building where this takes place. Some secondary schools can provide both lower secondary education and upper secondary education (levels 2 and 3 of the ISCED scale), but these can also be provided in separate schools, as in the American middle school- high school system.
Secondary schools typically follow on from primary schools and lead into vocational and tertiary education. Attendance is compulsory in most countries for students between the ages of 11 and 16. The organisations, buildings, and terminology are more or less unique in each country.