I applied online through Facebook's careers site, to my surprise I was contacted on my cellphone about an hour after I submitted my application by a Facebook recruiter, he asked me a little bit about my background, about my visa status, and then setup a phone screen for the day after where he told me he was going to make more in depth questions about computer server, this phone called lasted less than 10 mins. The next day I've got the call and it was a 30 min interview, I was asked more in depth about my previous experience, and some more questions about servers. At the end of the call he told me that he was going to share his notes with the engineering team and they'll make the decision if they wanted to move forward with me or not, by this time I already knew that this was a long shot, since my background wasn't a right fit for the kind of questions he was asking. Two days after that, I've got the rejection mail thanking me for my time and letting me know that my background doesn't fit that position, which I kind of already knew. The entire process took 4 days, so that was pretty fast, and the recruiter was always professional both on the phone and in email.