Use the Save command to copy the current file to disk.
 
  When you save a file with the Save command, it retains
  its name (the title at the top of the window). The
  saved version overwrites any previous versions with
  that name.
 
  You can continue to work on a file you have just saved;
  it remains open.
 
  TIP: To avoid overwriting the previous version of a
  file, use the Save As command rather than Save.  With
  Save As, you can rename the newer, changed version.
To save a disk file
 ┌─────────────────────────────────┐
 │                                 │ ■ Accept this name
 │ File Name: ▒▒▒▒▒▒▒▒ ◄───────────│── or type a new name
 │                                 │
 │ C:\XXX    ◄─────────────────────│─■ File will be saved
 │                                 │   in this directory
 │ File List:         Drives/Dirs  │ ■ Select directory or
 │ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒   ▒▒▒▒▒▒▒▒▒▒▒ ◄│── drive name
 │ ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒   ▒▒▒▒▒▒▒▒▒▒▒  │ ■ Existing files are
 │        ▲                        │   listed
 │        └────────────────────────│─────┘
 └─────────────────────────────────┘