How to prohibit a post from showing at the front page

I’ve found 2 articles on the same subject.One is the official one that you also reffered to and another article that suggest that I should use only one condition in my if.

Official codex article:
if ( $query->is_home() && $query->is_main_query() )

Other site (http://premium.wpmudev.org/blog/how-to-exclude-category-from-wordpress-homepage/) article :

if ( $query->is_home )

So what solution do you suggest that I follow?
Thank you!