PWM technically be the pulse-width modulation (also known as PWM stands for pulse-width modulation) of a signal or energy source. It is a technique in which the duty cycle of a periodic signal (a sine or a square, for example) is modified, either for transmitting information through a communications channel or to control the amount of power that is sent to a load. Pair

Within the different types of electrical cables we can find single or multifilament cables. The difference lies in the number of conductors that make up the cable. Single wire cables contain only a single conductive wire, whereas multi-wire cables contain more than one wire. Do not confuse multifile (A) or single wire (B) with monopolar (C), bipolar (D) or multipolar (E) cable. Monopolar cables have only oneSingle conductor, bipolar cables have two conductors, while multi-pole cables have more than two conductors. It may be said that any unipolar, bipolar or multipolar cable can be single-ended or multi-stranded. In the case of single wire cables we will talk about rigid cables, whereas the multifilament cables will be flexible.
In the following table you can see the difference between them.

It is called an rpm (revolution per minute) to the unit that is used to express the angular velocity. It is the number of complete turns a body gives around an axis.