Documentation should explain the concept of "background class"

The use of background classes isn’t mentioned in the documentation. This was one of the strategies that users at eNTERFACE17 used to overcome classification and regression problems.

Recommendation: This is one concept that should be explained as it has a significant practical impact when setting up the classes and training the model. It would be beneficial to introduce it by using a Venn diagram with the "complement of a set", and relating this to the design space and design language

@rebeccaf Mentioned that Nick Gillian wrote about this, check this out.