From Tim Berners-Lee
Date: 1998, last change: 2013-03-04 22:56:21

When you design a system or a language, if the features can be broken into relatively loosely bound groups of relatively closely bound features, then that division is a good thing to be part of the design. This is just good engineering. It means that when you want to change the system, you can with luck in the future change only one part, which will only require you to understand (and test) that part. This will allow other people to independently change other parts at the same time. This is just classic good software design and books have been written about it. The corollary, the TOII is less frequently met.