In Synapse, the default learning design hierarchy is Course > Lesson > Topic > Asset.
The Course represents the entire training experience. It is the sum of all the lessons and topics that you design.
Lessons contain topics that correspond to the learning objectives. Lessons can have one or multiple topics associated with it.
Topics contain raw assets that will make up the content the learner sees.
In this example, the topic has an embedded YouTube video as an asset.
Assets can be different types such as Editor (including text, charts and lists), Attachments, or Embed.