Summary

This chapter introduced the concept of web feeds, providing you with a basic understanding of what they are and what they can mean to your organization. Important things to consider before either offering or consuming feeds, such as security, legal concerns, and server load, were introduced.

XML, the language that presents feeds, was introduced, along with the accompanying terminology (root element, parent, child, valid, and well-formed). Keeping these rules in mind will be vital when producing feeds, because errors may not be immediately apparent but will make your document inaccessible to the public. Two additional considerations were also mentioned as a contrast to HTML: Capitalization counts with XML and repeated white space characters are not ignored.

Finally, the most common feed formats were introduced — RSS 0.91, 1.0, and 2.0, along with Atom 0.3. These formats (and often RSS in particular) are often treated as synonyms for web feeds, so at least a passing understanding of their layout is required. These specifications continue to be discussed in the next few chapters.

Overall, the major goals of this chapter were as follows:

• Introduce the concept of feeds as well as their use

• Present major considerations when using feeds

• Provide enough information on the XML format to allow you to continue to use XML in future chapters

• Introduce major feed formats

The next few chapters all build on the knowledge gained here. Chapter 3 concentrates on retrieving data from feeds provided by others, and Chapter 4 introduces the concepts involved in developing your own feed.