Really Simple Syndication (RSS) Programming Interview Preparation Guide

RSS (Really Simple Syndication) is technology that can be used on Websites to syndicate and distribute frequently updated content via news aggregators.

Syndication benefits both users and publishers by helping users consume more information instead of visiting multiple web sites to see what's new, users can scan headlines or article summaries and click to read the full text. Some publishers also make their entire content (whether full-text or audio/video) available for users to access via RSS and view in other applications. It's "really simple" for publishers to make content available in this format.

RSS is also a special XML based language used to create RSS files on Websites that contains headlines or summaries of news, or site contents to allow news aggregators to fetch and redistribute.

XML (Extensible Markup Language) is a generic markup language to organize generic information into a structured document with embedded tags.

RSS (Really Simple Syndication) is an extension of XML designed to organize headlines of news or summaries of Web pages to feed to news aggregators.

For more information on XML, please visit http://www.w3.org/XML/.

RSS is relatively new. Many versions have been developed in recent years:

► RSS 0.90 - The earliest known version of RSS released to the public by Netscape in 1999. RSS 0.90 is based on RDF (Resource Description Framework). When RSS 0.90 was created, the RSS initialization stood for Rich Site Summary and not Really Simple Syndication.
► RSS 0.91 - Developed by UserLand in 2000.
► RSS 1.0 - Published as a proposal by a group led by Rael Dornfest at O'Reilly in 2000.
► RSS 2.0 - Released through Harvard under a Creative Commons license in 2003.

Atom is an XML-based document format that describes lists of related information known as "feeds". Feeds are composed of a number of items, known as "entries", each with an extensible set of attached metadata. For example, each entry has a title.

The current version of Atom is Atom 1.0. For more information, please visit http://www.ietf.org/rfc/rfc4287.txt.

Main differences between Atom 1.0 and RSS 2.0:

► Atom has separate "summary" and "content" elements, while RSS only has one "description" element.
► Atom standardizes auto-discovery in contrast to the many non-standard variants used with RSS 2.0.
► In Atom, it is mandatory that each entry have a globally unique ID, which is important for reliable updating of entries.
► Atom 1.0 allows standalone Atom Entry documents whereas with RSS 2.0 only full feed documents are supported.
► Atom specifies that dates be in the format described in RFC 3339. The date format in RSS 2.0 was underspecified and has led to many different formats being used.

The Web browser and Website syndication industry has adopted a standard icon to identify syndicated content as shown below:
Syndication Feed Icon

A RSS 2.0 file looks like the sample RSS 2.0 document below:

<?xml version="1.0"?>
<rss version="2.0">
<channel>
<title>Developer HTML Tutorial and Tips</title>
<link>http://www.globalguideline.com/html/</link>
<description>Massive collection of frequently asked
questions by developers with clear answers and
tutorials tips.
</description>
<language>en-us</language>
<pubDate>Sat, 1 Jul 2006 04:00:00 GMT</pubDate>
<webMaster>noreply@globalguideline.com</webMaster>
<item>
<title>CSS Tutorial Tips</title>
<link>http://www.globalguideline.com/css/</link>
<description>A collection of FAQs on CSS and Atom
introduction and generation of feed files.</description>
<pubDate>Sat, 1 Jul 2006 04:00:00 GMT</pubDate>
<guid>http://www.globalguidelinecom/xml/</guid>
</item>
</channel>
</rss>

An Atom 1.0 file looks like the sample Atom 1.0 document below:

<?xml version="1.0" encoding="utf-8"?>
<feed xmlns="http://www.w3.org/2005/Atom">
<title>Atom FAQs, Tips and Tutorials</title>
<subtitle>The first Atom document example</subtitle>
<link href="http://www.globalguideline.com/faq/rss/"/>
<updated>2006-07-13T18:30:02Z</updated>
<author>
<name>globalguideline.com</name>
<email>noreply@globalguideline.com</email>
</author>
<id>urn:uuid:60a76c80-d399-11d9-b91C-0003939e0af6</id>
<entry>
<title>Introduction to Atom</title>
<link href="http://globalguideline.com/faq/rss/index.html"/>
<id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
<updated>2006-07-13T18:30:02Z</updated>
<summary>A collection of 7 FAQs to introduce you the
basics of RSS and Atom for Website syndication.</summary>
</entry>
</feed>

Atom is an XML-based document format that describes lists of related information known as "feeds". Feeds are composed of a number of items, known as "entries", each with an extensible set of attached metadata. For example, each entry has a title.

The current version of Atom is Atom 1.0. For more information, please visit http://www.ietf.org/rfc/rfc4287.txt.

XML (Extensible Markup Language) is a generic markup language to organize generic information into a structured document with embedded tags.

Atom is an extension of XML designed to organize headlines of news or summaries of Web pages to feed to news aggregators.

For more information on XML, please visit http://www.w3.org/XML/.