They will do check your basic domain knowledge,which depends on job requirement & skills need for the required technology.Above all you should maintain good communication skills & inter personal skills.Stages are screening,technical check,pay negotiation.

Conducting introductions. The first stage of the interview process is meeting the hiring manager and exchanging introductions. Making conversation. Gathering information. Performing the interview. Concluding. its better to reach there reqirements with sufficient technical knowledge.