No, they are not the same as CGI. You can run PHP as a CGI, as many cheap hosts do, but for performance PHP is run as either Apache mod_php or php-fpm with Ngin

No, they are not the same as CGI. You can run PHP as a CGI, as many cheap hosts do, but for performance PHP is run as either Apache mod_php or php-fpm with Nginx. Mod_perl is not CGI and requires much more discipline to prevent shared memory leaks. Mod_perl allows content negotiation which CGI does not.