Here's a look at some notable birthdays being celebrated today:

Chely Wright
Age: 41
Occupation: Singer and Songwriter
Known For: Charting more than 15 singles on the country charts, writing songs for other artists such as Brad Paisley, Richard Marx, Indigo Girls, Mindy Smith, and Clay Walker, and being the first major country music performer to publicly admit she's gay

Katy Perry
Age: 27
Occupation: Singer and Songwriter
Known For: Hit singles such as 'I Kissed a Girl,' 'Hot n Cold,' 'California Gurls,' 'Teenage Dream,' and 'Firework,' being the first female artist to get five songs on the Billboard Hot 100 in one year, her bizarre fashion sense, and her marriage to comedian Russell Brand

Marion Ross
Age: 83
Occupation: Actress
Known For: Playing Marion Cunningham, aka "Mrs. C," on the sitcom 'Happy Days' from 1974 to 1984

Bobby Knight
Age: 71
Occupation: Retired College Basketball Coach
Known For: Winning more NCAA Division I men's college basketball games than any other coach, his long stint as Indiana University's coach, and his famously violent temper

Helen Reddy
Age: 70
Occupation: Singer
Known For: Fifteen Top 40 singles in the 1970s including 'I Am Woman,' 'Delta Dawn,' 'You and Me Against the World,' and 'Angie Baby'