The Shudra - The Producers. They are the people that work, that toil. They have nothing but their own labor and skill at developing and producing a good or service. They are the working class. they derive their wealth from being ever more productive, or by producing a higher quality good.They may elevate themselves to the level of a craftsman. For their work they are able to buy goods from the Vaishya

The Vaishya - The Traders. They sell what they don't produce. They buy from the shudras, and then sell to others. Their primary job is to sell locally, if not regionally, if not nationally, if not internationally. Although, they provide a service to the people because they interlink communities into bigger and better connected markets, so they do a lot of travelling. They tend be wealthier than the shudra community.

The Kshatriya  - The Police. They are in charge of orderliness in society. They ensure that the lower two castes behave, are civilized towards one another, they ensure that social norms are followed, and then punish people who do know follow the law. They also protect the whole society from outsiders who wish to do harm to the locals. They are paid in taxes. When they do their job correctly, business can flourish even more.

The Brahmanas - The Learned. These are the people who are in charge of giving the policies for the Kshatriya to follow. They spend all their time reading learning and understanding the sacred texts to know what kind of laws their ought to be. They are the Legislators.