说明：  可以作为TCP协议栈的服务端，向网络节点发送数据，在发送的过程，将要发送的文字、数字、符号进行了编码转化，最终以比特数据发送出去，并采用了一些防止误码的检测算法，以便于接收端判断数据的开始和结束。配套有客户端，原理与之相反。
(It can serve as the service side of the TCP protocol stack, send data to the network nodes, code, convert the text, numbers and symbols to be sent in the sending process, and finally send out bit data, and adopt some detection algorithms to prevent errors, so that the receiver can judge the beginning and end of the data.)