difference between JCO connection and JCO connector

Dear All,

Can some one please tell me the difference between the JCO connection(Index.html->webdynpro tools->maintain JCO connection) which is i know used for connecting between systems in EP as like RFC in ABAP system & the JCO connector(irj/portal->system administration->System landscape) and also their difference in functionality.

Thanks & Regards,

Rajdeep