From Penny’s new flames through to Stuart, the comic book store owner, we’ve grown to love pretty much every character that’s walked onto the set of The Big Bang Theory.

However, have you ever wondered what the people behind the characters are actually like in real life?

John Galecki as Leonard Hofstadter – Then

Leonard is an original cast member, appearing on the show since the airing of the pilot. His character is the best friend and roommate of fellow star, Sheldon Cooper. The pair work at a university where Leonard is an experimental physicist who often comically gets annoyed at his best friend, but ultimately  always ends up forgiving his behaviors.

His neighbor across the hall,  the beautiful and cool Penny, captures Leonard’s heart from the beginning of the show, with the two finally marrying during the ninth season after years of on-off dating.

John Galecki as Leonard Hofstadter – Now

In real life, John was involved in many projects before he landed a starring role on The Big Bang Theory. However, none of them exploded in the same way as Leonard did. Audiences could not get enough.

The character has won John many awards, including an Emmy for the leading role in a comedy television series. When season eight was in the works, John renegotiated his salary from $350,000 per episode, to nearly $1 million.

Alessandra Torresani as Claire – Then

Claire is the cute bartender, that meets Howard and Raj at Stuart’s store. She asks Raj to help write her sci-fi movie she is working on for children. Raj thinks there is chemistry between them, but Claire doesn’t share the same feelings.

She is shocked by the fact that Raj split with his Emily to pursue a relationship but then later calls him to ask him out. Claire dates Raj at the same time as Emily, but Raj ends up breaking up with them both.