There are three categories that product placement in movies fall into. Visual, audio, and plot placements. The terms themselves are pretty self explanatory.
Visual Placement
Visual placement is when a brand or recognisable product appears on screen. Not all visual placements are the same. How prominent a brand is in a visual placement is determined by factors like the style of the camera shot, and the number of on screen appearances. Visual placements include outdoor advertisements in urban scenes or food brands in kitchen scenes.
Audio Placement
Audio placement is when a brand appears on the audio track. Generally this means the brand is mentioned in the dialogue by a character. The prominence of an audio placement is determined by a number of factors. The context the brand is mentioned in. The frequency at which the brand is mentioned. The emphasis put on the brand name (tone of voice, place in dialogue, who the character speaking is, etc).
Plot Placement
Brands or products can only show up in movies in two ways. Seeing them or hearing about them – visual and audio placements. A plot placement can be visual or auditory or a combination of both. What makes it a plot placement is the level of connection the brand has with the story or a character. The more central to the plot, or identifiable with a character the brand is the higher the level of intensity the plot placement has.