What is RSS?

RSS stands for “really simple syndication,” or, depending on who you ask, “rich site summary.” At their heart they are just simple text files with basic updated information — news pieces, articles, that sort of thing. That stripped-down content is usually plugged into what is called a “feed reader” or an interface that quickly converts the RSS text files into a stream of the latest updates from around the web. 

As internet content became more complex, so did RSS files, which quickly adopted images, video, and more, but still in a stripped down format for easier loading and compatibility across all feed readers. Readers usually automatically update, so that they delivers the newest content right to your device. Basically, this approach allows internet users to create their own online feed filled with custom updates from the sites that they like to visit regularly.

Here are some of the screenshots:

https://www.digitaltrends.com/computing/what-is-an-rss-feed/