Survey via email to external users

hi,

     I need to know how send survey via email to external mail ids. I want to attach survey url in the mail and the response of the mail need to be captured in the system.

     For instance, there is a survey url, how will this be access by customers if a mail them this survey and how will i attach the response suppose to an activity in system.

     Another doubt is when we generate url, there are get option : bsp, http, https, can anyone please help me understand how this works and how to get file for https

Regards,

Priyanka T