PHP session variables to temporarily store the member's username and profile picture data when they log into the website. You will need to locate those session variables in the PHP source code

Can anybody please point out which folder and file these or in

thanks

Also what does this mean ?

The code below is a standard iframe code to place the chat client SWF into your website. Simply add the code highlighted in orange to pass the username and profile picture data you got from your exisiting member system to the chat client SWF. The chat client will automatically connect members with their username and profile picture and skip the initial login screen. 

<iframe src="chat.swf?username=   orange code >(<?PHP echo $user ?>&picture=<?PHP echo $picture ?>" width="860" height="550"></iframe>) < the orange code is in the brackets

Does it mean add the code in orange to username and profile picture data ?