RSS stands for Really Simple Syndication or Rich Site Summary. It is a web feed that allows users and applications to access updates to online content in a standardized, computer-readable format. RSS feeds can include headlines, summaries, and links to full articles or webpages. RSS enables users to stay informed about the latest content from their favorite websites without needing to visit the websites individually. It is commonly used by news websites, blogs, podcasts, and other online publishers to distribute their content efficiently.