Answer:
Mahayana Buddhism is the largest Buddhist sect in the world, and its beliefs and practices are what most non-adherents recognize as "Buddhism" in the modern era. It developed as a school of thought sometime after 383 BCE, possibly from the earlier school known as Mahasanghika, though that claim has been challenged.
Mahasanghika ("Great Congregation") was an early Buddhist school that developed after the Second Buddhist Council of 383 BCE when the Sthaviravada school ("Sect of the Elders" or "Teaching of the Elders") broke away from the Buddhist community over doctrinal differences. This early schism led to others and the development of many different Buddhist schools of which Mahasanghika was only one.
