When we press Enter, F5 or Ctrl+F5 to refresh a webpage, is there any difference among them? Actually it's yes, we can find the difference from the request header and response header information.There are two cases about pressing Enter in the address bar. First if the page requested is cached and not expired in the browser, we can find the header information sent by the browser is :Host 192.168.3.174:8080User-Agent Mozilla/5.0 (Windows NT 5.1; rv:5.0) Gecko/20100101 Firefox/5.0Accept text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8Accept-Language zh-cn,zh;q=0.5Accept...