The criterion for the classification of contents of education is the content of education received.
The classification of fields of education is based on the UNESCO International Standard Classification of Education ISCED 1997, which is intended for classifying all education according to their level and content field.
The ISCED classification contains nine single-digit level broad fields and 25 two-digit level narrow fields. Typically, the 2-digit level of the classification of fields of education is used in international data collections.
A 3-digit separate classification (Fields of Education and Training; Detailed fields) has also been developed for fields of education and training to meet specific data collection needs and to clarify classification to the 2-digit level. The 3-digit level classification is also intended for national purposes, and it is used especially in countries that do not have their own national classification of education.
All education irrespective of level of education can be classified with the classification of fields of education.