"There is nothing as practical as good theory" - Kurt Lewin :)
The LAMP stack (Linux OS/Apache internet server/MySQL DBMS/Perl PL) consists of 10 million lines of code [Neville-Neil 2008], interacting in myriad ways to achieve impressive functionality and performance. But the main principles are : good engineering design practices have been followed; requirements were defined and met; rigorous testing and debugging has taken place