An Introduction to ROR (Resources of a Resource)

For example if your website is selling products, ROR enables you to document your product names, descriptions, prices, images, availability, affiliate programs, etc. Or if your site or blog provides information on a given topic, it allows you to describe how this information is organized (sitemap, topics, categories, new information, archive, blogroll, etc). ROR also provides terms for documenting objects such as contacts, articles, newsletters, feeds, images, audio, links, reviews, privacy policy, copyrights, and more.

ROR FileROR information can be easily added to your website by adding a ROR File called ror.xml. ROR is actually quite simple. It is built on top of RDF, the W3 Resource Description Language (http://www.w3.org/RDF). If you are not familiar with RDF, don't worry, we won't go into any details here.

With ROR, all objects are represented by a <Resource> tag, and can optionally have a <type> property to determine the type (or class) of the object (e.g. Product, Article, etc). The other properties are determined by the type you choose. Here is a simple example of a Product object described by ROR:

<Resource>      <type>Product</type>      <title>My Product</title>      <desc>My great new product</desc>      <url>http://www.my-web-site.com/my-product.htm</url>      <price>19.95</price>      <currency>USD</currency></Resource>

Pretty simple, isn't it? And if you want to describe other objects, ROR provides other types like Contact, Article, Feed, Event, etc. You can find the current list of object and their properties in the ROR Specification at http://www.rorweb.com/spec.htm.

Now let's see how to assemble several objects together in a ROR file. In a ROR file the meaning of information is determined by both the objects and the relationship between them. Depending how an object is linked to another object, it will provide a different meaning. To link two objects together the property resourceOf is used. Here is an example:

<Resource rdf:about="object-1">      <title>Object 1</title>      ...</Resource>

<Resource>      <title>Object 2</title>      ...      <resourceOf rdf:resource="object-1"></Resource>

<Resource>      <title>Object 3</title>      ...      <resourceOf rdf:resource="object-1"></Resource>

The first object uses the rdf:about attribute to identify itself so it can be referenced elsewhere. The resourceOf property is then used to attach the second and third objects to the first. Attaching the two objects to the first one is a way to say that they contain information that relates to or further describes that object.

That's pretty much it! Now that you know the essential about ROR, let's create a simple ROR file. Again we won't go into the details of RDF, but let's just say this; since ROR is built on top of RDF, it is enclosed in the <rdf:RDF> tag. Notice that the main object of the file has a type property set to Main. This is common in a ROR file, it provides an entry point into the data structure of the ROR file.

<rdf:RDF       xmlns="http://rorweb.com/0.1/"       xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">

<Resource rdf:about="mysite">      <type>Main</type>      <title>My Website</title>      <url>http://www.my-web-site.com</url>      <desc>My great site with a ROR file to describe it<desc></Resource>

<Resource rdf:about="products">      <type>Product</type>      <title>My Products</title>      <url>http://www.my-web-site.com/myproducts.htm</url>      <currency>USD</currency>      <resourceOf rdf:resource="mysite"></Resource>

<Resource>      <type>Product</type>      <title>Product 1</title>      <url>http://www.my-web-site.com/product1.htm</url>      <image>http://www.my-web-site.com/product1.gif</image>      <price>19.95</price>      <resourceOf rdf:resource="products"></Resource>

<Resource>      <type>Product</type>      <title>Product 2</title>      <url>http://www.my-web-site.com/product2.htm</url>      <image>http://www.my-web-site.com/product2.gif</image>      <price>29.95</price>      <resourceOf rdf:resource="products"></Resource>

</rdf:RDF>

Extending RORTo make it easier to use, ROR provides a set of pre-defined objects. These are objects that are commonly used on websites (Contact, Address, Webpage, Product, Feed, etc). But ROR is designed with simplicity and flexibility in mind, it can be easily combined with other vocabularies. As a simple example, let's say you want to describe a list of people. To do this you can combine ROR with the Friends of a Friend (FOAF at http://www.foaf-project.org) vocabulary. Here is what you would get: http://www.rorweb.com/examples/members.xml

ROR ToolsThe ROR website (http://www.rorweb.com) offers several tools to help you create a ROR file. The ROR File Editor makes it easy to create and update a simple ROR file without any coding. The File Reader allows you to create a ROR file from a tab-delimited text file with your products, articles, links, or contacts information. This tools can also read a Froogle product feed or a Yahoo Shopping feed. Finally, the ROR Explorer allows you to drill down into the information of a ROR file.

Happy RORing!