keyring是一种用于保护PALM中关键信息的系统，保护的数据包括用户名、密码、信用卡号等-keyring is a PALM China for the protection of critical information systems, protection of data including user name, password, credit card number, etc.

本系统主要实现ATM提款机的主要功能，包括系统自动识别卡号，验证用户信息（如果输入的密码三次错误时，系统自动扣留本信用卡），查询当前用户信用卡的余额，修改用户密码，打印清单，取款等功能。-The system is mainly to achieve the main function of ATM cash machines, including automatic identification card system to verify user information (if you en