The band model (band theory) is a quantum-mechanical description of solids in which the closely spaced energy levels group into bands, and electrons occupy these bands. It is used to explain the very different electrical behaviour of conductors, insulators, and semiconductors. The key factors are the filling of the highest occupied band and the size of any gap above it.

能带模型(能带理论)是固体的一种量子力学描述,其中密集的能级聚成能带,电子占据这些能带。它用于解释导体、绝缘体和半导体迥异的电学行为。关键因素是最高被占据能带的填充情况及其上方能隙的大小。