My last house was 120 years old, and the wiring was terrible, with ancient knob-and-tube conductors and lots of ungrounded, ...

A light switch is the simplest of electrical devices. Flip the switch, electricity flows. Flip it again, electricity stops. Lights on, lights off. That’s great for a small room with one entrance.

Have no fear—affinity diagrams are here to save you from getting overwhelmed by the sheer volume of data you’ve gathered. They’ll help you navigate through and organize your data in an incredibly ...