This document discusses amplitude modulation (AM) transmission. It describes how AM works by impressing a low frequency information signal onto a higher frequency carrier signal, changing its amplitude. This modulation process produces an output waveform with frequencies at the sum and difference of the carrier and modulating signal frequencies. The bandwidth of an AM signal is defined as twice the highest modulating frequency. Phasor diagrams and equations are provided to illustrate how the carrier and sideband signals combine to form the AM envelope. The coefficient and percentage of modulation are defined as measures of the amplitude change in the modulated signal.