Monthly Archives: December 2006

RSS, OPML and Metaphor

There are many explanations of RSS and OPML at the conceptual level, for example, here and here.  Not too many people want to digg their physical realization, which is XML, though XML is human readable.  Conceptual model is more important for people to further leverage these two standards.

We’ll try to explain them here using metaphor.  Hope it’ll help understanding them easier.

1.  Comparing with TV.

RSS is summery of individual channels.  And OPML is the channel (TV Guide Channel) for other channels.   Every RSS contains one CHANNEL and may have many ITEMS.  From TV perspective, ITEMS are PROGRAMS.   On the cable TV at my home, the channel for other channels is 22, which outlines program information about what is going on in other channels.

2.  Comparing with a research paper.

RSS item is abstraction part of a research paper.  OPML is reference part of a research paper.  For example,

Understanding Data Through Analysis of Structured Markup and Usage

Steven J. Altschuler; Edward Jung; Lani F. Wu

November 1999


Data and documents with semantic markup (such as in XML) allows for the construction of usage models that are human interpretable. A framework for performing analysis over semantic markup data in conjunction with usage information is described along with applications for performing automated clustering and “find-similar”. A strong emphasis on “human interpretability” is placed on the results of these analytical techniques.

Keywords: XML, interaction history, semantic analysis, clustering, pattern lattice”

It contains title, authors, publish date and abstraction is the short description.


S. Chu, G. Ellis, Investigating Lattice Techniques for Organising Document Collections, In the 4th International Conference on Conceptual Structures, ICCS’96, 1996  (RMIT University, Australia).Paul S. Jacobs, ed., “Text-based Intelligent Systems”, Lawrence Erlbaum Assoc., New Jersey, 1992Yezdezard Zerxes Lashkari, Feature guided automated collaborative filtering, Thesis (M.S.), MIT, Program in Media Arts & Sciences, 1995.

J. H. Van Lint, R. M. Wilson, “A course in combinatorics”, Cambridge University, 1992.


This reference (or bibilography) part outlines other research papers, similar to OPML.

3.  Comparing with web site.

RSS is summery of an individual web pages.  OPML is the sitemap.  From this perspective, “Rich Site Summary” is a better name than “Really Simple Syndication”. 

OPML is the architecture of a system of knowledge

Two approaches:

1. Semantic Web talk by Tim Berners-Lee at XML 2000: Semantic Web Architecture

2. Jim Moore:  “Knowledge is the new free. What does this mean? It means that the timber of intelligent action is abundant and at hand. The challenge for us is not so much “how to know,” as “what to do” with our knowledge. What design considerations will we apply to our houses of knowledge? Will our stick-built mansions of knowledge be sustainable? Will they harmonize with the planet? Will they contribute to peace and mutual understanding across the vast diversity of human values and life styles? Will our particular mansions hold together, keep out the rain, shelter us from the winds, and allow us to make a home for our families?

OK, what in the world does this have to do with OPML?

OPML is a language for assembling sticks and timber of knowledge into useful systems that can be shared with others, that can be improved upon by a community, and that can be published to the entire online world at almost no cost.

OPML is the architecture of a system of knowledge. An architect of a stick-built home expresses a vision in plans. She draws floor plans (top view), elevations (side view), and specialized drawings for electrical, heating and ventilation, and so on. Similarly, OPML structures, as we will see, are used to assemble valuable pieces of knowledge that are wildly scattered across the web. Just as architects of buildings constantly consult books of materials and catalogues of lighting fixtures, heating systems, roofing materials and windows, architects of the web are masters of locating rich sources of potentially relevant knowledge. The artistry of OPML is to combine sources in an appropriate and elegant manner. “

Defensive Patents

If I spend so much time, effort and money to get a patent, why do I give up protection by declaring it for defensive purposes?  Maybe it’s time for patent office or another organization to set up another category, which requires much less time and money.

Widgets are GUIs for RSS Processing

A few predictions indicated widgets will be big in 2007.  For example, Mashable’s 2007 Predictions. To me, widgets are GUIs for RSS Processing.

Year 2007 Prediction: RSS Processing Everywhere

If we see RSS everywhere in year 2006, it’s reasonable to predict we’ll see RSS processing everywhere in year 2007.

First of all, I use “Processing” instead of “Read”, though “Read” is one type of “Processing”.  Since RSS is structured data, it allows us to do more than “Read”.  That’s why I think “Read/Write/Execute” makes sense.

Certainly, the best way to predict future is to invent it.  That’s what we are working on it.  Hope we can make our service available in the next a few months.

Year 2006: RSS, RSS, Everywhere

From structured data perspective, year 2006 is the year for us to see “RSS, RSS, Everywhere” on the web.     

Read, Write, Execute

Gartner predicts blogs may be peaked in 2007.  That’s not likely to be true.  People will start to blog their executable code and the results of these executable codes. 

See one of “Five Predictions for Enterprise 2.0 in 2007” on FASTforward blog:

“5.  User-generated applications will become the next hot thing.  If Web 1.0 was “read only” and Web 2.0 is “read/write,” the next logical growth phase will be “read/write/execute.”  User generated applications will emerge that allow users to tie together web services to dynamically create custom functionality without having to know anything about programming or development.  Big winner:  Teqlo. “

Subscriptions Like Mine

If you sign in and upload your OPML, you can get a list of “Subscriptions Like Mine”.  Interestingly, Brad Feld, Jeff Barr, DeWitt Clinton, Dave Winer are in the list of mine.

OPML and Knowledge Sharing

I found this OPML about business rules and rule engine blogs from  I believe OPML represents this piece of knowledge quite well.  Then I imported this OPML to my Google Reader.  So this knowledge is shared quite efficiently.

RSS and OPML Blog List contains a list of blogs for RSS and OPML. It’s created by Marjolein Hoekstra.