Posts about Star Schema.
A dimension table isn't just a lookup. Why fact-to-dimension relationships have to be many-to-one, why bidirectional filtering always causes problems, and how to build dimensions your DAX can trust.
Most introductions to star schema start with the diagram. The star, the centre, the spokes. This one starts with the question: what problem does a fact table solve that a flat table doesn't? Part 1 builds the intuition before the vocabulary, so the rest of the series makes immediate sense.