Web design course - From the document-oriented view the redundancy and opacity
From the document-oriented view the redundancy and opacity could be seen as bugs in the system. However, if we turn things around into a different model, magically the bug becomes a feature and what was opaque becomes transparent. Item-Oriented Models The document-oriented view is a fairly direct analogy of the traditional paper publication. But rather than consider the feed as a package, if you think of it more like a source of continual information, it takes on some different characteristics. Twenty-First Century Press Clippings One of the less glamorous jobs in the old media of newspapers is clipping. For a very long time, certain publishers and press clipping services have offered a selective view of relevant media to their customers. Say your company is in the environment-friendly lawn mower business. You ll probably want to know what s going on elsewhere in the world of environment-friendly lawn mowers. You could read every newspaper and periodical in your area or even internationally, but that wouldn t leave much time for lawn mowers. So you could get some poor souls to do the reading for you, extracting any articles or advertisements of interest with a pair of scissors. At the end of every week you d get a pile of individual clippings, all about lawn mowers. The material in such a system would be treated at the granularity level of the articles of course you d want to know the source of each clipping, but that information is auxiliary to the article itself. Afeed can be thought of as a kind of clipping service, except the clippings are available in real time, immediately after they appear. Your aggregator will visit each feed periodically to collect the clippings. Where this analogy is weak is in that current systems are rarely as specialized or personalized as a press clipping service. Such services do exist: PubSub.com will provide a feed based on the results of a custom search query. In fact, the following is the address of a feed of search results on the keywords environment-friendly lawn mowers : http://rss.pubsub.com/37/b5/3778cec38f25c9f8282681622a.xml PubSub is ahead of most of the field in this respect, but in general the idea of treating individual clippings (that is, syndicated items) as standalone, self-contained pieces of information is very powerful. Microcontent and Memes Information can appear in many formats, and traditional print media tends to favor large chunks: books, magazines, and academic papers tend to be multipage collections of text that cover wide areas. However the tendency on the Web has been toward smaller pieces, and the newsflash or blog post represents the ultimate in granularity. Essentially you will have a single idea or meme, with a few lines of human-readable content backed by several pieces of machine-readable metadata. It is believed that this approach to information will offer better personalization (you only get the information you want) supported by more efficient search and organization of these small chunks of information. The stereotype of this is of course the syndicated item. Being able to extract individual items from a feed enables the manipulation of information at this meme level. Which leads us to the entry or item-oriented model of feed data. Figure 20-4 shows the general idea. Items are detached from their originating feed, although they commonly will include a back reference to the source feed. The aggregator in its truest sense is a tool that aggregates items from a variety of sources. 247 Modeling Feed Data
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