Cyanocobalamin is the most common and widely produced form of the chemical compounds that have vitamin B12 activity.
For example, the hadron constituents of atomic nuclei, neutrons and protons, have charges of 0 e and +1 e respectively; the neutron is composed of two down quarks and one up quark, and the proton of two up quarks and one down quark.
To try to make things easy, many books, articles and websites will tell you that protons are made from three quarks (two up quarks and a down quark) and draw a picture like the one shown in Figure 1. The neutron is the same, but with one up quark and two down quarks, as also shown in Figure 1.