<P> Caste - based differences have also been practised in other regions and religions in the Indian subcontinent like Nepalese Buddhism, Christianity, Islam, Judaism and Sikhism . It has been challenged by many reformist Hindu movements, Islam, Sikhism, Christianity, and also by present - day Indian Buddhism . </P> <P> New developments took place after India achieved independence, when the policy of caste - based reservation of jobs was formalised with lists of Scheduled Castes and Scheduled Tribes . Since 1950, the country has enacted many laws and social initiatives to protect and improve the socioeconomic conditions of its lower caste population . These caste classifications for college admission quotas, job reservations and other affirmative action initiatives, according to the Supreme Court of India, are based on heredity and are not changeable . Discrimination against lower castes is illegal in India under Article 15 of its constitution, and India tracks violence against Dalits nationwide . </P> <P> Varna literally means type, order, colour or class and was a framework for grouping people into classes, first used in Vedic Indian society . It is referred to frequently in the ancient Indian texts . The four classes were the Brahmins (priestly people), the Kshatriyas (also called Rajanyas, who were rulers, administrators and warriors), the Vaishyas (artisans, merchants, tradesmen and farmers), and Shudras (labouring classes). The varna categorisation implicitly had a fifth element, being those people deemed to be entirely outside its scope, such as tribal people and the untouchables . </P> <P> Jati, meaning birth, is mentioned much less often in ancient texts, where it is clearly distinguished from varna . There are four varnas but thousands of jatis . The jatis are complex social groups that lack universally applicable definition or characteristic, and have been more flexible and diverse than was previously often assumed . </P>

What are the four types of caste system in india
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