There is no fixed definition of traditional folds. We may also call it classical folds. Instead of trying to give a well-defined notion to some class of conventional origami, we present here typical fold methods of traditional origami. Generally, traditional folds allow us to construct origami more complex than by Huzita-Justin folds.
Our starting point in this direction of R&D is the following article we published in
T. Ida and H, Takahashi, A New Modeling of Classical Folds in Computational Origami. pp. 41 – 53, EPTCS 352 Proceedings of the 13th International Conference on Automated Deduction in Geometry Hagenberg, Austria/virtual, September 15-17, 2021, Editors P. Janičić and Z. Kovác.