This is a copy of the slides for a talk I give as a Distinguished Lecturer for the IEEE EMC Society. In this presentation, I review three important SI topics: Characteristic Impedance, Differential Impedance and Inductance. We look at why these topics are confusing and then how to think about them to feed your engineering intuition so you can use these important concepts to solve signal integrity problems. For more information about the Distinguished Lecturer series, check out the IEEE.org web site.