1st round focused on general technical knowledge and cultural fit 2nd round was a technical interview focused on systems design and conceptional understanding of technical principles. 3rd and 4th rounds were more cultural and behavioral focused.

I just had one phone call with HR, we had a call setup at 11:AM, but HR did not call and called me at 11:25 and she seemed to be in a bad mood and did not even ask me if this is a right time to talk? ( common sense ) What kind of culture is this? the HR conversation was not smooth, it was very rough like the way HR was asking questions to me.