The Big Bang Theory is not just one of the longest-running TV comedies in US television history—it’s a pop-culture phenomenon ...

The CBS sitcom followed a group of best friends and roommates and also starred Kaley Cuoco as Penny, Jim Parsons as Sheldon Cooper, Johnny Galecki as Leonard Hofstadter, Simon Helberg as Howard ...

The Big Bang Theory built a big universe around its central leads, but this set of characters was noticeably absent for most of the series.

His EMI algorithm, an early form of artificial intelligence that he developed in the 1980s, prompted searching questions ...

In the 17th episode of the debut season of "The Big Bang Theory," something huge happens: Leonard Hofstadter (Johnny Galecki) ...

For twelve years and the same number of seasons, Chuck Lorre and Bill Prady's CBS sitcom "The Big Bang Theory" absolutely ...

Johnny Galecki is a dad! The "Big Bang Theory" star, 44, announced the birth of his son with girlfriend Alaina Meyer on Instagram Wednesday by way of a sweet picture of the baby's tiny hands ...

The 50-year-old actor starred as the experimental physicist and love interest to Leonard Hofstadter (Johnny Galecki) from 2007 to 2010, and was downgraded from main to recurring cast in 2009.

The series followed best friends, roommates and physicists Sheldon Cooper (Jim Parsons), Leonard Hofstadter (Galecki) and Howard Wolowitz (Simon Helberg). Galecki’s Leonard married Cuoco’s ...

He went on to say that her relationship with the two series leads, Leonard Hofstadter (Johnny Galecki) and Sheldon Cooper (Jim Parsons), made her particularly successful. “She was never ...

“The magic of Kaley was, Kaley’s character — as we figured this thing out on the fly — was amused by [Jim Parsons’ Sheldon Cooper and Johnny Galecki‘s Leonard Hofstadter], was not critica ...

CBS Photo Archive / CBS via Getty Images As far as most people are aware, the first episode of the series introduces main characters Sheldon Cooper (Jim Parsons), Leonard Hofstadter (Johnny ...