网络编程中浏览器向服务器发请求时里包含的Host信息啥意思，不解
import java.io.*;import java.net.*;class ServerDemo { public static void main(String[] args) throws Exception { ServerSocket ss = new ServerSocket(11000); Socket s = ss.accept(); InputStream in = s.getInputStream(); OutputStream out= s.getOutputStream(); String ip = s.getInetAddress().getHostAddress(); System.out.println(ip); //看看浏览器向服务器发送过来的是什么信息 byte[] bt = new byte[1024]; int num = in.read(bt); System.out.println(new String(bt, 0, num)); PrintWriter pw = new PrintWriter(out, true); pw.println("<font color = 'red' size = '4'>欢迎访问百度主页：www.baidu.com </font>"); s.close(); //ss.close(); }}