RSS stands for Rich Site Summary, meaning "site summary" or "concise site content." It allows you to stay updated with the latest news and titles from your favorite websites and blogs without the need to visit them individually.

The main uses of RSS are: Displaying the latest titles from other websites on your own site and vice versa (content sharing). Receiving the newest articles from your favorite sites using special software (more efficient web browsing).

Without RSS, you would need to manually check your favorite sites every day to stay updated. With this technology, you can gather feeds from multiple sites in one program called an RSS Aggregator or RSS Reader, and view the recent post titles without visiting each site.

What is an RSS Reader? An RSS Reader is an electronic software application that reads RSS feeds. There are many such programs available for download, and recently, web browsers have also integrated RSS reading features. Some well-known RSS readers include Thunderbird and Google Reader.

refrence: wikipedia