Trending: Happy 21st Birthday Ariana Grande!Today, Ariana Grande turns 21 years old and we think the only "Problem" she is going to have is figuring out whether or not to get a martini or margarita tonight. I say get both. #YOLO
Happy 50th Birthday UCF!Today is an important day in Orlando as The University of Central Florida turns 50!
Tweet Beat: It's Harry Styles' Birthday!
Happy Birthday, Justin Timberlake!
One Direction and Justin Bieber Tweet Happy Birthday To Niall HoranAnd how has Niall actually spent his birthday? Let's Twitter track!
Happy Birthday, Beyonce!As the singer celebrates her special day we take a look at some of her best looks over the years.
For His 35th Birthday: Our Favorite Kanye West Tweets
Happy Birthday Adele
Birthday Breakdown: Top 10 Songs To Celebrate 50 Cent's 36th Birthday