Hi all.... If we use SEO code containing links and text as a comment in the footer of the page(not visible on site), then does it cause penalization to our site by search engines or it helps in SEO?
It depends what you mean by "seo code", do you mean you're using lcoaking. If so, it is very bad for SEO.
Yes code and links not visible will get you in trouble. Whether it is hiding by CSS or simply making the text color the same color as the background.