Hindu Religion is so wide that it is very difficult to know everything about it. It has many religious books: some are available here too:

1. Tulasee Daas Jee's Raam Charit Maanas

2. Vaalmeeki Raamaayan

3. Shree Mad-Bhaagvat Puraan

4. Hindu Puraan and Upanishad

5. Krishn (in Hindi poetry)

There are many Hindu religious sites on Internet. 

In the same way there are many very common festivals celebrated in India all round the year. It is said that there are 370 festivals in India - means there are even more festivals than the number of days in a year. Some of the main festivals observed in North India are described here for general information.

There is a short Glossary too to understand some Hindi and English religious terms.