The expiration time of cookie? is artificially specified; the remaining time can be calculated using ?, and php? can only be obtained simply by appending auxiliary? cookie? variables.

session?The expiration time is?0 and does not need to be considered.

Session uses a daze time. By default, it will expire if the user does not operate for more than 20 minutes.

There are generally two types of cookies. 1. If the expiration time is not set, it will be stored in the memory and will become invalid when the browser is closed. 2. Set the expiration time, which will be stored in the hard disk and will not expire until the expiration time.