Their meanings are as follows:
MQS: Modular Quadlock System, Modular Quad Plug System, is a connector system commonly used in the automotive industry, usually used to connect harnesses and devices in the automotive electrical system.
MCON: Modular CONnector is a versatile connector system for a variety of applications, such as automotive, medical, industrial, and communications.
MCP: Multi-Contact Pro Series, Multi-Contact Point Connector, is a high-density connector system with excellent signal transmission performance for applications such as high-speed data transmission and signal processing.
These terminal classifications are TE's own product families, each with its own specific design and application scenarios.