Why is the lowest group called the Untouchables?

The lowest group in the Indian Caste System is called the Untouchables due to the historical belief that they were so impure that contact with them would contaminate higher castes. Traditionally, they were assigned tasks considered unclean or polluting, such as manual scavenging or handling dead bodies. This led to severe social stigma and discrimination, with Untouchables often being marginalized and excluded from mainstream society. The term is now widely recognized as derogatory, and efforts continue to promote social equality and rights for these communities.