How do I stop the timeout of sessions and make session time infinite? (PHP) -

I am using OpenID (LightOpenID) with PHP and I can not help but notice that Session is a short period of time, and this is a problem. How can I increase the limitless session session? I have looked at many ways but I do not believe I am adding code in the right places. If I need to paste my code, just say so, but I did not think it was needed. All help is greatly appreciated! :)

  `& lt ?? Php if (! Isset ($ _ session ["timeout"])) {$ _SESSION ['timeout'] = time (); }; $ St = $ _SESSION ['timeout'] + 120; // Time of session is 2 minutes, changing this price can help you if (time ()) & lt; $ St) {Echo will be 'last 2 minutes of session'; }? & Gt; `