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
We need an object for our affections We need an object for our affections, something identifiable on which to focus attention. But in a typical office building, to what can we attribute the all-pervasive comfort of 70ºF, 50% relative humidity? Most likely, we would simply take it all for granted. When thermal comfort is a constant condition, constant in both space and time, it becomes so abstract that it loses its potential to focus attention. Lisa Heschong, Thermal Delight in Architecture It's cold outside, but this room is quite cozy love