These are all Open Graph protocol tags. The OG protocol is a metadata standard introduced by Facebook, and understood by many other online platforms like Twitter. While they won't help you with standard search engine indexing and ranking, your website will definitely benefit from them, because they tell Facebook and others how to interpret and display your content, making it more attractive when it is shared. For standard search engines, continue to use standard, all purpose meta tags we all know and love.
The Open Graph protocol documentation shows that the first meta tag you listed,
og:sitename, is listed under optional but recommended properties. It is basically recommended for object metadata, such as audio and video files:
og:site_name - If your object is part of a larger web site, the name
which should be displayed for the overall site. e.g., "IMDb".
(Note the underscore in
The other two,
article:section, are also optional, and mostly used for articles. No vertical is specified in the documentation, so they can be used with any article.
A great CSS-Tricks article about social media meta tags, while a couple of years old, is still relevant. There was also a similar (but not duplicate) question asked on this message board.