RSS (Rich Site Summary, RDF Site Summary, or Really Simple Syndication) is a format created to more easily deliver frequently updated content to users, such as blogs, news, company information, site announcements, job information, and shopping information. With RSS, users can easily and conveniently receive updates about new posts without having to visit the site.
Additionally, RSS files can be used to collect various information from websites. RSS files created according to RSS specifications contain information from specific sites. (For example, Site B's operator can collect various information from Site A (such as updated post titles, links, main content, etc.) through RSS files and post them on their Site B. This way, Site B visitors can easily know the latest changes on Site A without having to visit Site A directly.)

The presence of this button on a page indicates that RSS service is supported.
It is displayed in various ways such as: XML RSS RSS | RSS 2.0 RSS | ENTRIES XML, Syndicate this site (XML)