Bernadette, played by Melissa Rauch, is a Cheesecake factory waitress that works alongside Penny.  Penny introduced her to Wolowitz and now the two are dating.

She's actually quite smart and is working her way through graduate school microbiology studies.

Bernadette Quotes

I'm the kind of girl who can get all the giant missiles she wants.

Bernadette

Penny: He wasn't intellectually stimulating enough.
Bernadette: Couldn't you just fool around with him and then listen to NPR?
Penny: Wouldn't help. Zack couldn't even spell NPR.

TBBT Quotes

Penny: Hey, Sheldon, did you change your Wi-Fi password again?
Sheldon: Yes, it's "Penny, get your own Wi-Fi." No spaces.

Penny, there's only one cookie with something in the middle that solves life's problems, and that's an Oreo. Or a Nutter Butter, if you're in a pinch.

Sheldon