RSS allows users to subscribe to websites and receive brief updates when new content is published, saving the time spent manually checking each site. When subscribing to an RSS feed, the user will see a stream of articles from that site in their feed reader. Aggregator programs collect RSS feeds from multiple sites in one place, allowing users to view headlines and updates from various sources like news sites and blogs together efficiently. RSS uses RDF and XML standards to define the format and tags for feed files to be read by aggregators.