According to Vedas the God is One. Can I know who is the "real" God ?.Are Vishnu , Shiva and Brahma all the manifestation of the supreme Paramatman ?? If Vishnu, Shiva and Brahma are the manifestation of Paramatman, what about Ganesha, Hanuman and Durga ?? Are they paramatman too ??
All of them can be seen as different aspects of the Paramatman serving different purposes:
There are three forces: Brahma shakti, Vishnu shakti, and Shiva shakti. You may have one of these predominant. Brahma shakti is the force to create something new. Vishnu shakti is maintenance and Shiva shakti is bringing in transformation, filling in life, or destroying.
Some of you have Brahma shakti. You may create well, but you may not be able to maintain. For example, you may make friends very fast, but it does not last long.
There are others who cannot create but are good at maintaining. For example, people have long lasting friendships but cannot make any new friends. In such cases, Vishnu shakti is dominant.
And then there are others who have more of Shiva shakti. They bring in new life or transformation or they can destroy the whole set up.
In Guru shakti, all three shaktis have blossomed fully.
So each of you first identify which shakti you have more of and aspire for Guru shakti. Guru makes a group but a group cannot make a Guru.
From an article by Sri Sri Ravi Shankar: http://www.artofliving.org/wisdom/knowledge-sheets/who-are-you-brahma-vishnu-mahesh-or-guru
Hope this helps! :)