What is a news feed?
A news feed (also known as an RSS feed) is a listing of a website's content. It is updated whenever new content is published to the site. News readers "subscribe" to news feeds, which means they download lists of stories at an interval that you specify (every 30 minutes, for example), and present them to you in your news reader. A news feed might contain a list of story headlines, a list of excerpts from the stories, or a list containing each story from the website (BlueDevil's news feeds contain story excerpts). All news feeds will have a link back to the website, so if you see a headline / excerpt / story you like, you can click on the link for that piece of content and will be taken to the website to read it.
What is a news reader?
A news reader (also known as a news aggregator) is simply a piece of software that you can use to read your subscribed news feeds. It is to news feeds what Outlook, Hotmail, and Entourage are to email
What is RSS?
RSS (Really Simple Syndication) is an XML-based format for sharing and distributing Web content, such as news headlines. Using an RSS reader, you can view data feeds from various news sources, including headlines, summaries, links to full stories.