Conventional electronics uses the electron charge flow as the basic component of the Boolean construction of states, but electrons has an intrinsic angular moment, called spin. There are two experiments that justify the presence of the spin: the division of the hydrogen spectrum lines and the Stern-Gerlach experiment. The Stern-Gerlach, in 1922, showed that a bundle of silver atoms passing through an increasing intensity magnetic field divides into two beams: all this leads to the proof that a single electron has an intrinsic angular moment and a magnetic moment. The electron therefore has an intrinsic angular moment, which is independent of the orbital angular momentum. The term spin should not be taken literally, that is, in the classical sense of a rotating sphere on itself. A rotating sphere around its axis produces a magnetic moment, but the intensity of this must be reasonable in relation to the size of the sphere itself.