Don't let the Embassies' websites fool you, there are a LOT of visa types one can get in India.
I got this from the "Application for Visa Extension/Return Visa/Multiple Visa Entry/Exit Permission", from FRRO Hyderabad.
The types are: Tourist, Business, Employment, Entry (x), Student, Journalist, Official, Yoga, Diplomatix [not my typo], Medical, PIO, Medical Attendant, Missionary, Research, Provisional Student, Return Visa, Stateless, Others.
You read that well, there is a 'Others' too!
One of the annoying things is that there is almost no documentation online about these visas, and how to get them.
But that begs a question: do we really need all of those? Can we merge Yoga, Medical, Medical Attendant and Entry (x) into Tourist?
Do we really need the Return Visa?
What about the Missionary Visa? After all, a lot of missionaries in India are... Indian citizens!