该程序是一个能够从pop3服务器中检查所有邮件，并且可以查看邮件内容，也可以删除邮件但是没有实现附件的接收，使用时需要设定服务器地址以及用户名和密码；-The program is a check from the pop3 server all the messages, and you can view the message content, you can delete the message but did not achieve to receive attachments, usi

建立了客户端和服务器端，可相互发送消息，查看好友是否在线等，实测可以使用(Set up the client and server, can send messages to each other, check whether the friends online, etc., measured can be used)