This paper will enable the user to understand the operation of switching and linear voltage regulators. The most commonly used regulating modes will be covered. For linear regulators, the Standard, Low-Dropout, and Quasi Low-Dropout regulators will be covered (along with circuit examples). In the switching regulator section, the Buck, Buck-boost, Boost, and Flyback topologies will be detailed. Some examples will be given of products available for the design and implementation of switching converters.