The term "e²/h" represents a fundamental constant in physics, specifically related to the quantum Hall effect. Here, "e" stands for the elementary charge, which is the charge of a single electron, and "h" is Planck's constant, a key quantity in quantum mechanics. The ratio e²/h is significant because it appears in the quantization of electrical conductance in two-dimensional electron systems. This constant is crucial for understanding phenomena in condensed matter physics, particularly in systems exhibiting topological insulators and quantum computing. The precise value of e²/h is approximately 1/137, which is also related to the fine-structure constant, a dimensionless number that characterizes the strength of electromagnetic interactions.