RSS (Really Simple Syndication) is a system of sending and receiving updates and other information from a central source to many users.
Very often, computer users find themselves regularly visiting the same sites. These might be news sites, blogs, forums, web mail, or something else. Usually, this requires redirecting a browser to each sites, then browsing the contents of that site.
The fundamental idea of RSS is to simplify this process by making the user’s computer collect all the updates from the user’s favourite sites in one place. That ‘place’ is a program on the user’s computer, called an RSS feed aggregator or feed reader.