This document discusses various mechanisms of charge transport and current conduction in metal-insulator-semiconductor (MIS) devices. It describes six main conduction mechanisms: 1) Schottky emission, which is thermionic emission over a surface barrier, 2) Fowler-Nordheim tunneling, where electrons tunnel from the semiconductor through the insulator, 3) Direct tunneling, where electrons tunnel directly through the insulator, 4) Poole-Frenkel emission, where trapped electrons gain thermal energy to move through the insulator, 5) Space charge limited conduction, which dominates at high voltages/fields, and 6) Other possible mechanisms like trap-assisted tunneling and ionic conduction. Equations are provided for some