Ctrl + C
Copy places selected items (files and folders) on the clipboard for subsequent pasting. The clipboard’s contents may be pasted into the source folder; copies of all items are created.
Copy does not delete the original files or folders.
Copying (and Pasting) files or folders from other locations (ie. not the same folder) detects collisions (duplicate names) and presents the usual dialog allowing replacement, if desired. Files or folders copied from the same folder are renamed - Copy of…, Copy (2) of…, etc.