Generally, a subweb will contain its own index.htm and images folder.It can be published as a part of a primary web, or, it can be given its own domain name and published as an independent web.
A sub web will have a url that looks something like: http://www.primaryweb.com/subweb/ OR http://www.subweb.primaryweb.com/
They can be used in instances where there are programs used that conflict with things in a primary web, such as a bulletin board.
We use them in web design a lot. We design a client's web, publish it as a subweb of our site, then when the client makes his or her final payment, we can then publish that subweb to his or her host as an independent web.
If you have a part of your site where you wish to allow only certain people, you can make it a subweb and assign a username and password for admittance.
What they were saying is, when you are publishing your website, if you wish to publish a subweb at the same time, all its folders will also be published. You have a choice whether or not to publish subwebs. If all you did was update the primary site, you would have no need to republish the subweb(s).
Sandy
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