Origin of caste system in India

What is the Caste system and how does it work? The word ‘caste’ derived from the Spanish and Portuguese ‘casta’, means ‘race, lineage, or breed’. The word ‘Jati’ originates from the root word ‘Jana’ which implies taking birth. And later ‘caste’ replaced it. The Sanskrit word for caste is ‘varna’ which means colour. Not only