What does it mean?

I often watch American TV drama.
I often watch American TV dramas.

Recentry,I wonder one sigh.
Recently, I saw someone make a sign with her hand that I didn't understand.

Some one bend both hadns's two fingers,forefinger and middle finger,and the other were grip.
The pointer finger and middle finger were extended, while the other fingers were clenched.

I think this sigh is used girl.
I think this sign was used by a girl.

Do you understand this sigh?
Do you know what this sign means?

I think you're talking about the "peace sign" or sometimes the "victory sign"
http://en.wikipedia.org/wiki/V-sign
✌ (is that right?)

It has a different meaning in different contexts... (and it's used a lot in Japan... young people are always taking photos with this sign...).