a php session and cookie management question

[sandyde2]

Hi all,

b4, i only use session. i dunno whether it is good or not,
i do not use the session control organization provided by
PHP but developed an individule session database table
because i have multiple variables for different kinds of
users, and i wrote a specified class to handle the session
case which worked pretty fine so far. However, i have to
add cookie into the system, which i did not touch for
several yrs.

I expect the net friends here could help me to analysis
my problem, introduce me a bit of cookie and especially
teach me whether it is necessary to check cookie in
every page or only in login page (since in the login
page i have a check box to choose whether the user wants
to use cookie for 3 days, something like that), and how
to improve the session/cookie organization on the base
of my system.

thanks a lot :)