Folders are a useful way of keeping surveys organised. You can use folders to archive completed surveys, and also to set surveys as templates for future use.
NOTE - If you place a shared survey (One that has had access shared between accounts via the user permissions functions) into an "Archived" folder, it will no longer appear in the survey list for the users who have been given permissions to it.
In the Browse Folders list, hover your mouse over the folder name which brings up the three dots (...) icon and click on the three dots. The following options will appear - click on what you want to do: