The problem with trees Many systems are organized hierarchically. The CERNDOC documentation system is an example, as is the Unix file system, and the VMS/HELP system. A tree has the practical advantage of giving every node a unique name. However, it does not allow the system to model the real world. For example, in a hierarchical HELP system such as VMS/HELP, one often gets to a lead on a tree such as: HELP COMPILER SOURCE_FORMAT PRAGMAS DEFAULTS only to find a reference to another leaf: Please see HELP COMPILER COMMAND OPTIONS DEFAULTS PRAGMAS and it is necessary to leave the system and re-enter it. What was needed was a link from one node to another, because in this case the information was not naturally organized into a tree. Tim Berners-Lee, Seeing With Fresh Eyes A City Is Not a Tree hierarchywww
Cool URIs don't change An Essay by Tim Berners-Lee www.w3.org What makes a cool URI? A cool URI is one which does not change. What sorts of URI change? URIs don't change: people change them. The User Interface of URLs www
Customers don't know what they want At the end of the presentation someone asked whether he thought they should do some market research to see what customers wanted. "No," he replied, "because customers don't know what they want until we've shown them." Then he pulled out a device that was about the size of a desk diary. "Do you want to see something neat?" When he flipped it open, it turned out to be a mock-up of a computer that could fit in your lap, with a keyboard and a screen hinged together like a notebook. "This is my dream of what we will be making in the mid- to late eighties," he said. They were building a company that would invent the future. Walter Isaacson, Steve Jobs The iMac