when you develop on a "domain", you put the files on a server, which is a computer running a webserver (like apache e.g). a webserver is nothing but a program. so you can install a webserver (and database server, whatever you need) on your own computer as well. this way you can skip the ftp uploading part, which takes a lot of time. you only have to put the files you are working on, in a directory which the webserver handles. so if you save a file you can reload the browser...

this is a tutorial for installing apache on windows: http://httpd.apache.org/docs/2.0/platform/windows.html

hope that helps, martin