The term XML stands for Extensible markup language which consists of rules which allows you to encode a document so that it can be understood by the machine. In other words, it refers to changing a document into machine-readable format. It is used in a number of web applications. The XML feeds are the feeds that use the XML language. The web feeds are basically a system by which a subscriber gets information about an update or change in the website they have subscribed to. For instance, if you are reading a newspaper online and need to keep updated with any changes or new information then you can subscribe through the XML feeds. This way the feed would inform you of the new update or change and you can easily get to know about it. The content provider needs to use a feed link on his website so that the visitors can subscribe to it. The XML feeds are basically used by the website owners to help the search engines know about any new updates. It enables them to know about it easily and the search engines do not have to use web crawlers on all the web pages again. Thus it is considered to be convenient and is therefore used by most of the website owners.