An inductor is a bunch of wires wound in such a way their electromagnetic fields interact. When the current flowing through the coil changes, the time-varying magnetic field induces a voltage that opposes the change in current that created it. If there is no change in current flowing through the coil, then the steady state response of an inductor matches that of a short circuit/wire.

As electrons flow through the wire, they are influenced by the magnetic field created by electrons flowing through neighboring loops. If the rate of electron flow is different in different loops, then the magnetic fields will try their best to align, causing the electron flow to slow or speed up, analogous to two magnets spinning by each other.

An inductor is *dual* to a capacitor.

- $v(t) = L \frac{d I}{d T}$
- $i(t) = \frac{1}{L} \int_0^t v(\tau) d \tau$