>I have a table with clients and all cliens has his number.
>
> # 001 - Marck
> # 002 - Mary
> # 003 - Carl
>
>
> Which is more programatically correct:
>
> To create a field that will contain the client number
> or use the own table recno () ?

To create a field that will contain the number.
If you use recno() and one day a record is deleted. Subsequent additions to table would be duplicating previous ids.
Cetin