Forms authentication cookie.

Question

Hi,

Forms authentication is used for an asp.net application and <sessionState timeout="20"/>
Now if I leave my appln idle for 20 min.I need to login again.This means my userID and pwd will be saved somewhere in my local system.please tell me the path where these details will be stored and how asp.net session Timeout identifies these values to restroy when appln is idle...

Thanks in advance...