The Quantum Hall Effect is a phenomenon observed in two-dimensional electron systems subjected to low temperatures and strong magnetic fields. In this state, the electrical resistance becomes quantized, meaning it takes on discrete values rather than a continuous range. This effect is crucial for understanding the behavior of electrons in materials and has implications for quantum physics. This effect was first discovered in 1980 by physicist Klaus Hasselmann and has since led to significant advancements in condensed matter physics. It also plays a vital role in the development of precise electrical standards, as the quantized resistance values can be used to define the ohm.