There are two main models for understanding marketing communications: the macromodel and micromodel. The macromodel outlines nine key factors including senders, receivers, messages, media, encoding, decoding, response, feedback, and noise. The micromodel examines consumer responses using models like AIDA (attention, interest, desire, action), hierarchy-of-effects, innovation-adoption, and communications. These models help ensure marketing messages reach the right consumers at the right time and place and motivate purchase.