Web feed (or news feed ) is a technique for the simple and structured publication of changes to websites (e.g. news sites, blogs , forums , wikis ) in standardized formats and is one of the pull media . In contrast to push media (for example newsletters that are actively sent by e-mail from the notifying service to the recipient's mailbox), the initiative for receiving messages with web feeds lies entirely with the recipient. After subscribing to a web feed, he can decide for himself which news he wants to retrieve and when.
Software on the server recognizes new entries and / or changes in the CMS and updates the feed file on the server based on them. The most common formats for web feeds are RSS , Atom, and XML . There are also CDF Microsoft and JSON feed since 2017. The format OPML , however, serves to collect more web feeds to this easily between different feed readers share. The abbreviation “RSS” is so common that it is sometimes used as a synonym for web feed. This is wrong, however, because RSS is one of several dissemination techniques that the term web feed collects as a generic term .
Often only a short message (e.g. a headline ) is sent via feeds , combined with an Internet address at which the full article can be read. However, it is technically possible and is practiced in some places to provide texts of almost any length via feed.
A note is usually added to the links in a feed, by means of which the CMS can recognize that the visitor to a page has got there via the web feed. It is common to implement this as a server request, such a link can then look like this:
By means of feeds, hierarchically processed data can also be made available that can be further used and evaluated by other computer programs. At the yr.no weather service, for example, this is done with weather data using the XML format, among other things .
For reading web feeds, there are special programs called feed reader . If the user wants to follow a certain web feed, he “subscribes” to it in a feed reader. The feed reader calls up the subscribed web feeds at regular, usually freely selectable time intervals and saves the links contained (some also the complete articles). The user can then view the collected articles in different ways: e.g. For example, unread articles only, articles per feed, or articles from all feeds.
There are different approaches to calling up, preparing and displaying the feeds: Some feed readers offer the option of displaying selected articles as bookmarks , saving them and / or sharing them with other people. For others, the functionality is part of an overall concept, as is the case with some e-mail programs . Mozilla Thunderbird , for example, has a built-in feed reader - the special feature of Thunderbird is that a permanently archivable e-mail message is created from each individual message in a feed. There is the option of either displaying the description supplied via the feed file in the news display area or loading the website of the article live.
Advantages and disadvantages
The provider cannot choose the readers, but in return does not have to worry about managing the reader base (for example with mailing list software ).
When subscribing, the reader does not reveal that he is observing the source and can more easily subscribe to or unsubscribe from sources by simply making the setting in his feed reader. The individual reading behavior of individual users can therefore only be tracked to a limited extent (for example using the IP address of the reader) - in contrast to links in e-mail newsletters , which often refer to the specific subscriber with a key number or in plain text form, who received the newsletter and called up the link in full in the browser. However, the user misses news if he does not regularly access the feeds he has subscribed to (especially for pages that publish a lot) - in contrast to e-mail newsletters, which are delivered and through the e-mail for so long without the user having to do anything - Providers are accepted for storage until the mailbox is full.
Web feeds simplify in combination with a suitable feed reader in particular the observation of a large amount of different sources such as blogs , in which, it is rare to changes, but updating the reader does not want to miss. However, the content of the feed is volatile , so that you can no longer find the content after a while. These are separate archiving measures are required, such as using a feed reader , which can store the messages permanently locally copying Livemarks to another bookmark folder of the browser or saving the feed file on your own hard drive.
- The Difference between Web feed and RSS Feed. ( Memento of April 13, 2011 in the Internet Archive )
- Heinz Wittenbrink: Newsfeeds with RSS and Atom. Galileo Press, Bonn 2005, ISBN 978-3-89842-562-9 . on-line