I am developing a web application (using PHP) and I am wondering what the best way is to notify users that someone updated their account information? The information that can be updated includes:
- First name
- Last name
- E-mail address
To be more elaborate, should the old or new email be used to send the account update notification? What information that was changed should be sent in the e-mail (ie: name, e-mail, password)? Is it necessary to have a activation e-mail sent if the e-mail address is changed? I should also note that the e-mail address is being used as the username.