Document library created in the SharePoint can be opened in the Windows Explorer. This is handy for bulk copying files from the network drive to SharePoint document library, for instance. Procedure is quite simple. You just need to click “Actions” in the standard view menu and then select “Show in windows Explorer” The separate file window will open. You can copy, move paste etc., in this window.
People sometimes complained that this does not work for him/her. It took me sometime to understand the reason. It turned out that this only worked at the root folder level in our installation of SharePoint 2003. In aother word, if you create a subfolder in the document library and you “desend” to this subfolder, you can not switch the view to explorer view. Solution to this is to always start at the root folder level. With the 2007 installation, this limitation seems gone.