Vim swap file
Vim swap file is a temporary file created by the open source Vim text editor, when editing a file. The file's name typically begins with ".", and ends with ".swp". The file is normally deleted when editing is complete, but may be left behind in the event of a crash or other abnormal termination.
Its main purpose is to periodically record unsaved changes made to the file. It also serves as a lock file. The file format is undocumented, and not necessarily portable.
Files begin with ASCII "