(1) what is the difference between web service and windows service?
Windows Services (previously known as NT Services) are those
continually running processes that you stop and start through the
"Services" Control Panel Applet. If you want something to run on
a machine, doing something useful some, most or all of the time,
/even/ when nobody's logged on to that machine, you're looking at
a Windows Service.
A WebService is /similar/ to an ordinary Web Page, except that it is
intended to be called /not/ by a user with a web browser, but by other
processes, potentially on other machines (and potentially running other
Operating Systems!). Each Operation within the [Web] Service
performs a single, sizeable and useful piece of work.
(2) Can web application use windows service?
Possibly, but it depends on how the Windows Service is written.
Certainly, the Windows Services I've written tend to be "black box"
processes, dedicated to a single task and not taking much notice of
what's going on around them.
It's more likely, I would say, that a Windows Service will make calls
to one or more Web Service(s).
(3) Does web application support client/server methodology in
webform?
(If I understand the question correctly, then...)
Yes. .Net Web applications are simply the "next generation" of
ASP, but with (supposedly) better integration with the client
- so long as it's Internet Explorer, no doubt ;-)
HTH,
Phill W.
