There are three rounds for the interview.
1st round for the Screening process
2nd round for the Technical knowledge
3rd round for the HR
In the first round their was a screening of the candidate whether he/she is eligible for the role or not.
After qualifying the first round immediately there is second round in which detail analysis of candidate knowledge and skills required for the role.
And once second round will be cleared then third and final round is there for the salary discussion & negotiation.