Inductive vs Resistive loads
1) Inductive loads use magnetic fields. Examples - Motors, solenoids, and
relays. If it moves, it's probably an inductive load.
2) Inductive loads can cause blowback voltage. Circuits should be protected
from this by diodes.
3) Blowback is caused by a surge of voltage created by the collapsing magnetic
field in an inductor.
3) Resistive loads convert current into other forms of energy, such as heat.
No risk of blowback.