Ajax调用：新ActiveXObject（“Msxml2.XMLHTTP”）和新ActiveXObject（“Microsoft.XMLHTTP”）之间有什么区别？

I hope both the object invocations are referring to the ActiveXObject. But why are we passing two different parameters to work in IE. 1. Msxml2.XMLHTTP and 2. Microsoft.XMLHTTPI hope both the object invocations are referrin