If the program does terminal interaction, make it output a short
notice like this when it starts in an interactive mode:

    EveryNasa Copyright (C) 2022-2023 Redume
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
might be different; for a GUI interface, you would use an "about box".