The caste system divides Hindus into four main categories - Brahmins, Kshatriyas, Vaishyas and the Shudras. Many believe that the groups originated from Brahma, the Hindu God of creation. The system divides Hindus into rigid hierarchical groups based on their karma (work) and dharma (the Hindi word for religion, but here it means duty) is generally accepted to be more than 3,000 years old.