Q
QA - Quality Assurance (a process that ensures that activities meet prescribed standards through a mechanism involving documentation, training, and enforcement)
QC - Quality Control (method of ensuring that activities, services, equipment, and personnel operate within established standards)
QL - Query language (a programming language which enables users to make requests of a database)
QoS - Quality of Service (a capability which allows a protocol to distinguish between different classes of messages and to assign a defined measure of service within a network system)
QSA - Qualified Security Assessor (individual providing an independent assessment of compliance with the payment card industry data security standard (PCI DSS))