ZipOutputStream password hashing?

Hi,

When I set a password with string "mrmamalulu" to the ZipOutputStream during compression, may I know what happens to the password after that?

public void CreateSample(string outPathname, string password, string folderName) {
     ...
     string password = "mrmamalulu";
     zipStream.Password = password;  // optional. Null is the same as not setting. Required if using AES.
     ...
} 

Is the password stored in a clear text? Is there any hashing involved on the password? If yes, what is the hashing algorithm used? (e.g. MD5, SHA, etc)

Many Thanks!

Best Regards,

MrMaMaLuLu