As the name implies, invisible files and folders are those that cannot be seen in the Finder, whether they reside on the desktop or in a window. Invisible files and folders have an internal flag set that tells the Finder not to display them.
A file or folder is typically invisible for a reason. Deleting or modifying one of them may cause unpredictable results. Unless you know the outcome of your modification, you should not make changes to an invisible file or folder.