This chapter provides an overview of Augmented Reality (AR) as a training tool in manufacturing sectors, with a focus on manual assembly procedures. The proposed analysis investigates the two main components of an AR training system, the content creation or expertise capture (i.e., authoring) and the content consumption or information conveyance (i.e., training), separately, as they are generally treated in the literature. Finally, we present a classification of information conveyance mediums in AR, a relevant topic particularly for AR usage in industrial context.