You can use Text-image Transitions to explain a set of related topics. For example, a technical drawing includes parts numbered with callouts. If this slide was an Image-Text Snippet, the learner would have to click each item to view its description. With Text-Image Transitions the page transition is automatic. Combined with an audio file, this functionality creates a presentation with a narrative.
For this feature, the course developer sets a transition time value to control the pace of the transitions.