10 Facts Only True Big Bang Theory Fans Know

Are you fan enough?

1. It's three knocks and a Penny, three times.

It's three knocks and a Penny, three times.

No more, no less. No matter what.

2. If you check the color of Sheldon's t-shirt, you can tell how he's feeling.

If you check the color of Sheldon's t-shirt, you can tell how he's feeling.

There's a theory that the shirts are linked to the Emotional Spectrum put forth by the Green Lantern franchise (where rage is red, greed is orange, fear is yellow, willpower is green, hope is blue, compassion is indigo and love is pink).

3. Penny has never been given a last name.

Penny has never been given a last name.

Executive producer Steve Molaro promised to never give her a last name. When she married Leonard, however, she took his name, but what is her maiden name?

4. The actors all learned to play the instruments that their characters play.

The actors all learned to play the instruments that their characters play.

Which means that Jim Parsons actually knows how to play the Theremin.

5. Penny's hairstyle may change, but her purse never does.

Penny's hairstyle may change, but her purse never does.

A last name is one thing, but come on guys! Give the girl a new purse.

6. The elevator was broken by Sheldon while he was saving Leonard from a jet fuel explosion.

The elevator was broken by Sheldon while he was saving Leonard from a jet fuel explosion.

It will never be fixed.

7. Leonard's glasses are just frames.

Leonard's glasses are just frames.

If they had glass in them, they'd reflect the studio lights, of course.

8. Penny's least favorite word is "moist."

Penny's least favorite word is "moist."

You'd think it was her own name as often as Sheldon says it, but no. Moist.

9. Kunal Nayyar is not Kumail Nanjiani.

Kunal Nayyar is not Kumail Nanjiani.

Although it's become a running not-so-funny joke that they get mistaken for each other quite a bit.

10. The whiteboard equations are written by a real scientist, so they should be correct.

The whiteboard equations are written by a real scientist, so they should be correct.

Feel free to double check them, though.