The early Buddhist schools are those schools into which the Buddhist monastic saṅgha initially split, due originally to differences in vinaya and later also due to doctrinal differences and geographical separation of groups of monks.
The original saṅgha split into the first early schools (generally believed to be the
Sthavira nikāya and the
Mahāsāṃghika) a significant number of years after the death of Gautama Buddha.
Later, these first early schools were further divided into schools .