Of the 104 elements of the periodic table, 79 are metals, 25 are non-metals, 13 of them have chemical elements, and 12 are dielectrics. The main difference between semiconductors is that their electrical conductivity increases significantly with increasing temperature. At low temperatures they act like dielectrics and at high temperatures they act like conductors. These semiconductors differ from metal: the resistance of the metal increases in proportion to the increase in temperature.