RSS (Rich Site Summary) is a format for delivering regularly changing web content. Many news-related sites, weblogs and other online publishers syndicate their content as an RSS Feed to whoever wants it.
The simple part is that by subscribing to a site’s RSS Feed, you will automatically get sent the stripped down version of a favorite website of yours. No more loading ads or other various graphics the site has to slow you down. Only the content and important links are sent to your RSS Reader, which is a program or browser feature that tells you when your favorite sites have updated their page with new information/content.
One of the biggest advantages of using RSS is that you don’t have to supply a email address and be afraid that it gets sold to email campaigners who will SPAM you to death. If you don’t like a subscription anymore, just remove them from your RSS reader and that is it.