RSS...

A RSS stands for a Really Simple Syndication and it's a format for spreading news and other web stuff. When you put whatever you want to send into a RSS and send it to someone else or their website, it's called a feed.
You can add a whole heap of stuff to a feed and each feed contains a list of items (an index) and each one is identified by a link to the content of your website. Most RSS feeds include a title for the link and a description of the content.
RSS feeds keep your audience totally updated without having to actually go to your site, for example, in a software company's website people can miss out on important tech articles or updates if they forget to check it but by feeding it to them they won't miss out.
Feeds are different from email because it's more like a link to your website but it also has a description to get people to want to read it.
Reading feeds is similar to using a radio, the station sends out programmes and you use the radio to pick it up at home. With RSS you send out your content in a RSS feed and subscribers use a newsreader to read it.
You can find the feeds you want to subscribe to by setting you reader with your preferences and it will collect the feeds you're interested in every time there is an update.