They see your resume. They test you to the point that everything in you have put in your resume is true. For example, if you have put a project in your resume, make sure you can explain every detail about your project. Another example, if you have put certifications in a domain, for example, Java, they question you about the topics of Java. Confidence in your answers, communication skills, your interests does is important. In summary, it's a technical + HR interview.