Answer:
RSS
Step-by-step explanation:
RSS stands for RDF Site Summary, it was later known as Really Simple Syndication.
It was widely spread in the past, and used in most websites as a way to automatically distribute information from website-website, or website-user. Although it has other functions, a very common one is the "subscribe to feed" orange bottom that appears in a lot of blogs and news sites, like the one in the picture! By clicking you can give your email address to the website, and receive recurrent updates about the site's activity.