Like already said somewhere else, I coded Oracle for quite some time. During my work I used Forms Designer a lot. For the people now knowing Oracle and the Forms Designer: it is a tool which enables you to easily create applications which can maintain data on an Oracle table. This is achieved by a so called "trigger concept". In modern system development, we would call that "event based development". Thus, you could give the name of a table and the columns you want to have edited and the "forms runtime" displayed this in a guy. When the user now changed data, different triggers where fired. If the user pressed "F10" for commit, the "commit-trigger" was fired. If the user deleted a row, the "delete-trigger" was fired. And there had been a lot of these triggers. So, all you had to do was to implement these triggers if you wanted to change the standard behavior (if you did not do it, the build in's ware fired). So if for example the "commit-trigger" fired, your "onCommit" procedure "fired" and you could e.g. update another table before you updated the triggered table. This trigger concept I missed on PHP so I decided to develop something like that myself. And that is the backbone what we call the pPHPlib today!
The second philosophy is security. One of my goals is: Never sacrifice whatsoever to security. This means that input is automatically checked for you and triggers/events fire where you can check and filter the data again. Before commits data is quoted (or prepared statements are used) to avoid SQL injection. And output is also escaped, so that tags show up as what they are and are not interpreted.
So in very short you can summarize it like that: "The pPHPlib is an event based application framework with heavy focus on security".