Hang around any electrical engineer long enough, and you’re bound to hear the word inductance tossed around.  Or perhaps if you’re hanging around people dealing with high-speed signals, an ugly little thing called “cross talk” might get mentionned a lot (hint: it has nothing to do with speaking in an angry voice to your troublesome PCB, or any uncomfortable attempt to proselytize it and save it from eternal damnation in a lake of molten solder).  If you’ve ever wondered what either of these terms mean (and how they’re related), you might find it worthwhile reading this relatively accessible ‘app note’ of sorts explaining what inductance is and why it matters: What Really is Inductance? (by Dr. Eric Bogatin)