When trying to understand ZDDs, an alternative to BDDs, I was wondering whether a quite different view on representing boolean functions would be interesting. I called this different view Internally Optimized Decision Diagrams (IDDs). As it stands it is in no way clear whether this alternative view would be beneficial to represent large boolean functions, especially because I have difficulties finding efficient algorithms for standard functions, such as “and” and “or”, but I will still explain the basic ideas.