4 rounds of interview, all completed within 30 min. Questions are relatively difficult, not surprised - because it's Facebook afterall. Interviewers are very professional and polite. Although I did not get the job but it was a good candidate experience as the questions were asked in a very professional manner and ended off well.

An interview process involves submitting an application, meeting with recruiters and managers, answering questions about skills and experience, completing assessments, and receiving feedback or an offer after evaluation. It's a simulation.