The Big Bang Theory isn't just about nerds and jokes — it's about friends.

With seven core cast members, there are a lot of different friendship combinations on the CBS comedy. Each of them comes with their own set of quirks, humor and reasons why we love those people being BFFs.

Amy (Mayim Bialik) and Bernadette (Melissa Rauch) are flirtatious and fun, even when Penny (Kaley Cuoco) isn't around. Howard (Simon Helberg) and Raj (Kunal Nayyar) are just weird while Leonard (Johnny Galecki) and Sheldon (Jim Parsons) love one another while still infuriating each other.

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To celebrate how close this gang has become, TV Guide ranked the top five friendships on the show and highlighted some of their very best moments. Which one is your favorite? Which one feels the most like you and your best friend?

The Big Bang Theory airs Thursdays at 8/7c on CBS.

(Full disclosure: TV Guide is owned by CBS)