Any Example on How to use Triggers in Web Application Project

Question

Dear Friends,
I have a requirement when a person insert some data throug a Web form,
then his details must be capture in a Table....and next time who ever changes the data then his details must be logged in a Log table...by which Admin will come to know who has created the data and who change it later.
what has to be done in Web form or Database???

please let me know.

Regards,
Aamir