A sandbox is where users can share and create different templates. You can post a link to your sandbox on your profile page. In this page, please post the link to your sandbox (it is not mandatory to make one) under the letter that corresponds to the first letter of your username. (ex. "Rainbowfartz's Sandbox" would be in the "R" category)
(these are PERSONAL sandboxes; these ones are free for viewing)
(there is a main sandbox)
Also, any manipulation or changes made to a personal sandbox can be traced back to you, so make sure that the only sandboxes you edit are yours and the public sandbox.