Phone call - just to verify your details, and schedule an interview schedule with HR
HR Interview - interview to better know you as a person. Basically the goal is to give personality to your CV, and ensure alignment of your attitude and aspirations with the company's values and principles.
Panel Interview - interview with managers in the specific department you're applying; can range between 2-5 people, depending on their availability.
P.S. If you were an intern, they can have you go straight to panel interview.