Now, for POLP:

• P: Principle
• O: Of
• L: Least 
• P: Privilege

POLP states that a client must be given access only to the information or functions that they need. POLP is one of the most important pillars for building secure applications, and it is widely adopted by cloud infrastructure vendors such as Amazon, Microsoft, and Google.

There are quite a few benefits when POLP is applied:

• Sensitive data is protected and not exposed to non-privileged users.
• The system can be tested more easily since the number of use cases is limited.
• The system becomes less prone to misuse because only limited access is given and the interface is simpler.

The software design principles that we have learned about so far are great tools. Although SOLID, DRY, KISS, POLA, YAGNI, and POLP seem to be just a bunch of acronyms, they are useful in designing better software. While SOLID principles came from the object-oriented programming paradigm, SOLID's concepts can still be applied to other languages and environments. As we work through the rest of the chapters in this book, I would encourage you to keep them in mind.

In the next section, we will go over several software quality objectives when designing software.