A school is an institution designed for the teaching of students (or "pupils") under the direction of teachers. Most countries have systems of formal education, which is commonly compulsory. In these systems, students progress through a series of schools. The names for these schools vary by country (discussed in the Regional section below) but generally include primary school for young children and secondary school for teenagers who have completed primary education. An institution where higher education is taught, is commonly called a university college or university.
In addition to these core schools, students in a given country may also attend schools before and after primary and secondary education. Kindergarten or pre-school provide some schooling to very young children (typically ages 3–5). University, vocational school, college or seminary may be available after secondary school. A school may also be dedicated to one particular field, such as a school of economics or a school of dance. Alternative schools may provide nontraditional curriculum and methods.
There are also non-government schools, called private schools. Private schools may be required when the government does not supply adequate, or special education. Other private schools can also be religious, such as Christian schools, hawzas, yeshivas, and others; or schools that have a higher standard of education or seek to foster other personal achievements. Schools for adults include institutions of corporate training, Military education and training and business schools.
In homeschooling and online schools, teaching and learning take place outside of a traditional school building.
The concept of grouping students together in a centralized location for learning has existed since Classical antiquity. Formal schools have existed at least since ancient Greece (see Academy), ancient Rome (see Education in Ancient Rome) ancient India (see Gurukul), and ancient China (see History of education in China). The Byzantine Empire had an established schooling system beginning at the primary level. According to Traditions and Encounters, the founding of the primary education system began in 425 AD and "... military personnel usually had at least a primary education ...". The sometimes efficient and often large government of the Empire meant that educated citizens were a must. Although Byzantium lost much of the grandeur of Roman culture and extravagance in the process of surviving, the Empire emphasized efficiency in its war manuals. The Byzantine education system continued until the empire's collapse in 1453 AD.
Islam was another culture that developed a school system in the modern sense of the word. Emphasis was put on knowledge, which required a systematic way of teaching and spreading knowledge, and purpose-built structures. At first, mosques combined both religious performance and learning activities, but by the 9th century, the Madrassa was introduced, a proper school that was built independently from the mosque. They were also the first to make the Madrassa system a public domain under the control of the Caliph. The Nizamiyya madrasa is considered by consensus of scholars to be the earliest surviving school, built towards 1066 AD by Emir Nizam Al-Mulk.
Under the Ottomans, the towns of Bursa and Edirne became the main centers of learning. The Ottoman system of Külliye, a building complex containing a mosque, a hospital, madrassa, and public kitchen and dining areas, revolutionized the education system, making learning accessible to a wider public through its free meals, health care and sometimes free accommodation.
The 19th century historian, Scott holds that a remarkable correspondence exists between the procedure established by those institutions and the methods of the present day. They had their collegiate courses, their prizes for proficiency in scholarship, their oratorical and poetical contests, their commencements and their degrees. In the department of medicine, a severe and prolonged examination, conducted by the most eminent physicians of the capital, was exacted of all candidates desirous of practicing their profession, and such as were unable to stand the test were formally pronounced incompetent.
In Europe, universities emerged during the 12th century; here, scholasticism was an important tool, and the academicians were called schoolmen. During the Middle Ages and much of the Early Modern period, the main purpose of schools (as opposed to universities) was to teach the Latin language. This led to the term grammar school, which in the United States informally refers to a primary school, but in the United Kingdom means a school that selects entrants based on ability or aptitude. Following this, the school curriculum has gradually broadened to include literacy in the vernacular language as well as technical, artistic, scientific and practical subjects.
Obligatory school attendance became common in parts of Europe during the 18th century. In Denmark-Norway, this was introduced as early as in 1739-1741, the primary end being to increase the literacy of the almue, i.e. the "regular people". Many of the earlier public schools in the United States and elsewhere were one-room schools where a single teacher taught seven grades of boys and girls in the same classroom. Beginning in the 1920s, one-room schools were consolidated into multiple classroom facilities with transportation increasingly provided by kid hacks and school buses.