An inductor is a coil of wire wound according to various designs, with or without a core of ferromagnetic material, to concentrate the magnetic flux resulting from current flowing in the wire.
Capacitors are electronic passive components designed by placing two conductive plates (usually metal) in close proximity with each other, separated using a dielectric . There are many different types of capacitor construction and many different types of capacitors with particular ratings and purposes.
The DC and AC abbreviations are used in many descriptions of electronic circuits to show us what type of current is used for the electronic device .To understand how to use these electrical signals you must know differences of AC vs DC electrical signals. The DC is a abbreviation from the Direct Current , in other words a DC current is a current that keeps its direction of flow .