The Big Bang Theory stars have forged a strong and rock-solid friendship.

So, what are the secrets of their tight-knit rapport on and off the camera?

The Big Bang stars revealed the secret, as reported in People Magazine.

One of the star's' top secrets is maintaining a normal life that they can possibly do.

In an interview with People, Simon Helberg said:

"Everybody's got their feet on the ground, so it doesn't feel that much different than day one,"

Kaley Cuoco said:

"You learn who to talk to, where to go and how to act,"

People reported that Cuoco has also learned to think out of the box to make things better:

"If you don't want to be photographed, don't go to The Ivy, and wear undergarments when you go out!"

Melissa Rauch happily said:

"A lot of us hang out. It's just a close knit group,"

"Kaley is the best at throwing parties. Mayim's the deep thinker, and Kunal is a big giggler. We all get along, and it's a nice family feel."

The Big Bang Theory stars forge a closer friendship through engaging in wonderful bonding moments. They are fond of getting together in meals, enjoying some take-out food.

Fans should be inspired by their favorite actors' drive and desire to maintain happy and healthy relationships. This act is a positive inspiration from Hollywood the public can look up to.