In this paper we will endeavor to familiarize you with concepts related to different transmission applications. Various notions of mechanics and geometry required to make a good selection of drive components will be presented. These fundamental calculation basics are often found in engineering reference manuals but they have been included to show how they can be applied to problem-solving with belt transmission applications. You are therefore encouraged to examine this chapter and do the accompanying exercises as groundwork for calculating critical factors encountered when installing drive components.