Php setcookie in registration

Okay sorry for the stupid questi开发者_Go百科on im a begginer, and i would like the opinion from a more experienced developer.

I am makin a really small real estate website.

the signup asks for the first, last name, the phone and email.

they can login with their email and password.

My question is it a good idea to save the last, first name, and phone in cookies at the registration and save the email in to a cookie when they log in?

And could please someone explain if not why?

thank you

cookies are saved on the clients machine and can be manipulated, i would only save a session id in one, and store the 'hard' data in a db.

It is better to use $_SESSION variables. Read this for more information: http://php.net/manual/en/ref.session.php