偶是新手,帮忙解释一下!

<%
Response.Expires = 0
Response.Expiresabsolute = Now() - 1
Response.AddHeader "pragma","no-cache"
Response.AddHeader "cache-control","private"
Response.CacheControl = "no-cache"
%>
能不懂这些用到网页上做做,能帮我每一句解释一下吗?