In all computer security contexts, user authentication is an essential thing. The most popular and simple type of user authentication method is to use the alphanumeric passwords. The reasons behind why the authors are using alphanumeric passwords are the simplicity in the case of use and implementation. In order to avoid the drawbacks has been shown by these type of passwords; graphical passwords can be used for the user authentication by the fact that, a person can memorize images more than characters. And graphical passwords are difficult to break using the common attack methods such as brute force attacks, dictionary attacks and social engineering attacks.