One of the first things you learn in electronics is how to identify a resistor’s value. Through-hole resistors have color codes, and that’s generally where beginners begin. But why are they marked ...

If you manage a New York apartment building, you’ve got to know where that water is flowing—for putting out fires and for upgrades, maintenance and inspections. With pre-war buildings and ancient ...

This article, originally posted on Sept. 23, 2019, was last updated on Dec. 3, 2025. Please note that these statistics aren’t updated regularly. Always check with your state’s hospital associations ...