;OOUI: Object Oriented User Interface [[mw:OOUI]]
;ORM: Object Relational Mapping = a database approach
;PCI DSS: The [[wp:Payment Card Industry Data Security Standard|Payment Card Industry Data Security Standard]] was created in 2006 to ensure that all companies that accept, process, store, or transmit credit card information operate securely. The framework is primarily intended to keep cardholder information safe. All companies handling this information must comply with PCI DSS, regardless of size. The framework is administered and enforced by the Payment Card Industry Security Standards Council.
;PDF: Portable Document Format = a widely used standard for representing documents electronically and print. [[PDF]]
;PEAR: PHP Extension and Application Repository = a collection of code started in 1999 to enhance the utility of PHP.