Linked from
The 46 pages that link to Electrical impedance, each with the reason it gives.
Voltage dividerNarrower topic: The divider works with impedances, not only with ideal resistors.
InductanceNarrower topic: Inductive reactance is one part of this broader circuit quantity.
OhmNarrower topic: The ohm also measures impedance, extending resistance measurement to AC circuits.
GyratorNarrower topic: Impedance is the quantity a gyrator transforms between its ports.