Thanks to Riccardo for this article, I’ve reproduced it below but there are some formatting probs which can be avoided by visiting this link.
Riccardo Magliocchetti, riccardo –at– datahost –dot– it
Getting into a software project code that has been developed by various people over years isn’t an easy task since it tends to dishomogeneity. Some factors need to be taken into consideration: people’s programming habits and level of knowledge, and the passage of time, which improves and refines technology.
This is true in international and long term projects which, thanks to free /
open source software, are now quite common. The process fortunately can be controlled by adhering to strict coding style guidelines and W3  standards.
But with projects that are often done in contributors’ free time and that consist of hundreds of thousands of lines of code, can often be difficult to apply these rules.