The Rig Veda is the oldest Hindu releigious book that describes different worldy power centers like fire, rain, wind and so on. People are affected by them. This descrives the past castless Hindu society placing the position of women high in society. There are 1028 hymns, some of which are still sung in religious ceremonies.
The Rig Veda is the actual realization of the past difficult societies where people struggled with hardships like fire, rain, draught with their prevalent knowledge. The idea shaped the vision of their life. As for example, the Veda starts with the praise to fire 'Agni' and deals the God of rain 'Indra' most. There are thirty three major and minor Gods with which people are affected like people are directly affected by fire and rain.
The Rig Veda is the reality of all human societies only in another form. Past Indo Iranian people lives according to the philosophy. When time passes, things changes, feelings change and philosophies change. Many new philosophes have emerged since the time of Rig Veda.