When you send your Web site to the Internet it gets placed on a "server" to be viewed by anyone who knows your URL, or Web address. Where the server places your files directly effects your Web address.
In Web Studio we allow you to place your Web site in the "root" of the server or in a sub folder to allow for multiple site uploads.
If your Web site address were www.mysite.com and you put your Web Studio Web site in the root directory then visitors will see your home page when they type in www.mysite.com in their browser's address bar.
In contrast if you decided to not upload to the root then you would have to add the name of your Web site file to the end of your URL to properly view the Web site. For example, if you named your site Picnic the correct Web address would be www.mysite.com/picnic.
By default Web Studio uploads to the root directory. To change this, uncheck the box next to "Upload this site to the root of the Web site".