[Mobhack]

Basic mode needs a password. It's more forgiving of file handling errors etc. Basic mode is the only mode that lets you play on different computers (e.g. play on your laptop when away from home on a trip).

Basic mode is all that is required for games between friends.

Secure mode requires to be played on the same computer, in the same slot, attempts to count loads and exits etc.

Secure mode is for competitions and similar.