A school is a public educational institution designed primarily to offer learning zones and learning environments specifically for the training of children under the supervision of qualified teachers. Most developed countries have hybrid systems of public education, which can be both compulsory and non-comparative. In such systems, children progress through a structured series of primary schools, intermediate schools, and high schools. All this means that there are several different levels or stages in a school, and children must gain different levels of education based on their aptitude and skill set.

In most advanced systems of schooling, children have to complete either the secondary or primary level, while they gain further levels of education in the form of either the tertiary or the fourtharies. In many countries, both children who are enrolled in formal schooling as well as those who have opted for extracurricular initiatives may be grouped together for a limited period of time in pre-school, nursery, kindergarten or primary school. This grouping is referred to as grouping in international schooling. While this facilitates early childhood education and training, the arrangement may sometimes result in differences in the learning environments of children belonging to different strata of the socio-economic spectrum.

The other kind of arrangement in international schooling occurs when students progress from primary school to the secondary school stage. Students from different countries can be grouped together for a limited period in any educational institution designed exclusively for students from that country. The benefits of such a system are that students from different countries might learn different subjects and share various experiences. They also get exposure to new cultures and leisure activities. This enables them to develop in different ways. However, students who are grouped together for any formal education are not allowed to progress to higher levels until they have completed at least one year of the regular pre-school education.

In some cases, parents prefer not to enroll their children in a formal education system. For example, parents who wish to impart knowledge of their native language on their children who live in a different country might decide to enroll their children in a pre-school education system. Pre-school institutions usually provide instruction in reading, writing, and speaking of the local languages. Some also offer instruction in cultural studies and education. These learning environments enable children to interact with other children belonging to the same country and to practice the same language in conversation.

A school is generally defined as an establishment or place of instruction, where teaching and learning occur by means of a system of rules prescribed by a government or a private body. The earliest definition of a school was in the 12th century as the college of St. Trinit de Praxis, situated in France. It was a college for boys, established to give them training for military service. A school quickly spread all over France and other parts of Europe and into Spain and Italy. Schools soon spread all over the world.

School is an instruction provided in the schools for imparting knowledge to the people. It includes teaching, instruction, learning, growth, development and socialization. A school includes instruction in any subject for any purpose such as giving practical knowledge, developing vocational skills, improving communication skills, enhancing leadership skills, providing knowledge for self-improvement or social motivation. This is common doctrine of schooling.