Describe the various two-port network parameters and their applications.

Two-port parameters characterize networks with input and output ports. Z-parameters relate port voltages to currents (useful for series connections). Y-parameters relate currents to voltages (useful for parallel connections). h-parameters mix voltage and current (used for transistors). ABCD parameters relate input to output quantities (cascade connections). S-parameters use traveling waves (RF/microwave design, 50-ohm systems). Choice depends on measurement ease and circuit topology.