NGINX defaults its web page location

[Lxw2015]

SETTING UP AN NGINX WEB SERVER ON A RASPBERRY PI says
"NGINX defaults its web page location to /usr/share/nginx/www on Raspbian."

in my case there is no  /usr/share/nginx/www but  /usr/share/nginx/html/index.html

so I change the contents of /usr/share/nginx/html/index.html . then I open my pi web. the contents of web has no change. why?

thanks

[Lxw2015]

found, this is thedefault web page.
/var/www/html/index.nginx-debian.html