Rating: 

That said, I found this a very interesting document. For people interested in understanding the basis of tags, and how to implement them in Perl or PHP this is a great resource.

Jim begins with delving into the definition of what a tag cloud is, weighted lists, and some other technologies that various sites use. There is a descriptive analysis of popular sites and their use of tag clouds or other technology that makes for interesting reading.

The coverage of perl vs php implementations is not balanced. With perl, Jim walks through the script example line by line so perl newbies can really understand what is happening. He describes the required dependent modules and what they do/contribute to the scripts. He doesn't do the same with the php examples. (This may be something that is fixed in the final version.)

One other part that is deficient in this document is CSS. Jim mentions CSS but doesn't really explain what it is. There is an assumption that the individual already knows. A pointer to more information would be good even if the scope of the document doesn't include CSS. It's fundamental to the concept of design in current implementations of websites, and so is highly relevant but I understand the lack of space in terms of length of the document.

I found the information about human functions and the math that graphs these functions and how to manipulate the resultant curves to something that shows interesting results _very_ interesting. It is the first time I have been exposed to these concepts.

Overall this is a great resource for those who are interested in building more knowledge about this much used technology of Web 2.0 sites. Resources like these really make the library subscription to Safari very worth it.