I am using PHP sessions to store tracking data across my pages for my site. The session is started with `session_start();`

By the way - this is not a login script. I am tracking the first page the user entered on, the date/time and a few other variables.

I store the information in a database, and finally redirect the user to a page using:

```
header("Location: ".$URLHERE);
exit(); 

```

A few questions about using sessions:

1. As I am not explicity closing the session after the redirect, does PHP delete session variables from disk - or do I have to handle this myself?

(I am concerned about datafiles building up on my Apache server)

2. Are there any security issues with PHP sessions? This isn't a login, but my scripts do rely on session variables to track information about that unqiue visit.

Thanks :)