RSS, or Rich Site Summary, is a format used by blogs and news sites to syndicate data automatically. This means that publishers can deliver web content, like news articles, that are newly published or frequently updated. Subscribing to RSS feeds allows users to receive content once it has been published, without having to visit the websites directly. Once a user has subscribed to an RSS feed, their browser will constantly monitor the site, and either notify the user, or download the new content.
Most websites that offer RSS feeds will have a link at the bottom of the webpage called RSS or RSS Feed. Sometimes they will have the RSS icon. Click on the link or icon and you will be shown the RSS URL, the web address associated with the RSS feed for that site. This is typically displayed on a new page, but sometimes it appears in a pop-up window.