Johnny Galecki stars in THE BIG BANG THEORY on CBS – Photo: Robert Voets/CBS ©2007 CBS Broadcasting Inc. All Rights Reserved.

Johnny Galecki  : Leonard

Date Of Birth: April 30th, 1975  Hometown: Bree, Belgium

Johnny Galecki is best known to television audiences for his role as David in the long-running comedy series "Roseanne," for which he won a Young Artist Award.

His television series credits also include a recurring role in "My Boys" and guest appearances in "Hope and Faith" and "My Name is Earl."

Galecki's feature film credits include  "Crystal," "Bookies," "Vanilla Sky," "Bounce," "Playing Mona Lisa," "The  Opposite of Sex," "I Know What You Did Last Summer," "Suicide Kings" and  "National Lampoon's Christmas Vacation."

He recently closed the Tony Award-nominated Broadway play "The Little Dog Laughed," for which he received a 2007 Theatre World Award for outstanding Broadway debut.  His other theater credits include "The Drawer Boy" and "Pot Mom," at Chicago's Steppenwolf Theatre, "The Member of the Wedding," for which he was nominated for a Joseph Jefferson Award and "Galileo."

Galecki was born in Belgium where his father was stationed while serving in the U.S. Air Force.  He was raised in Chicago, Ill., and currently lives in Los Angeles.  His birth date is April 30.