I changed my Facebook profile picture just now after my boyfriend took a really nice photo of me today. We are now watching how much "likes" I'm getting, and he said it could be related Poisson Distribution. I didn't recall the exact details of Poisson distribution, so I looked it up: generally, it seems that poisson distribution is an appropriate model for events that are independent and occur in constant rate. In this sense, I guess Facebook "likes" can be modeled by Poisson distribution. Although I learned Poisson distribution and memorized the formula for its probability density function, etc., I've never had a chance to think of it in terms of real-life application.