Inductor — a passive electrical component, consisting of a coil with wire, which is designed to use the relationship between magnetism and electricity as a result of the passage of electric current through the coil

Inductor Symbol

Inductors resist or oppose changes of current. This ability of an inductor to resist changes in current and which also relates current,  with its magnetic flux linkage, as a constant of proportionality is called Inductance which is given the symbol L with units of Henry, (H) after Joseph Henry.

Inductance coils are used in the construction of various circuits with frequency-dependent properties, in particular, filters, feedback circuits, oscillatory circuits. Two or more inductively coupled coils form a transformer. They are also used for radio communication — the reception of electromagnetic waves, rarely — for the emission of waves.

First of all, we need to understand what is current and voltage and how do they work.

Current — This is the physical process of directed movement of charged particles under the action of an electromagnetic field from one pole of a closed electric circuit to another. Electrons, protons, ions and holes can act as charge transporting particles. In the absence of a closed circuit current is not possible. Particles capable of carrying electrical charges do not exist in all the substances in which they exist, are called conductors and semiconductors. And substances in which there are no such particles are dielectrics.

Voltage — To force charged particles to move from one pole to another, it is necessary to create a potential difference between the poles, or — Voltage. The unit of voltage is Volt. In formulas and calculations, the voltage is denoted by the letter V.

Resistance — the opposite concept of conductivity. The conductors conduct current differently. Their conductivity depends primarily on the material of the conductor, as well as on the cross section and length. The larger the cross section, the higher the conductivity, but, the longer the length, the lower the conductivity.

Electricity flows in two ways: either in an alternating current (AC) or in a direct current (DC).
The difference between AC and DC lies in the direction in which the electrons flow. In DC, the electrons flow steadily in a single direction, or «forward.» In AC, electrons keep switching directions, sometimes going «forward» and then going «backward.»

Hello everybody.
For the successful creation of devices, you need to understand the principles of its components.
During the semester, I will publish here articles on concepts and components of electronics and the principles of their work.
I hope they will be useful to you.
If you have any suggestions, please leave them in the comments.