Use a dollar bill to measure. Every piece of US paper money in your wallet/pocket/sock is 6" long. Folded in half, and you have a 3" measuring stick, and so on. I can't tell you the number of times ...

The pupillary distance (PD) measurement is a requirement for people who want to purchase eyeglasses. Here, find out how to measure your PD using a mirror and a ruler. Share on Pinterest Some eyewear ...

A Golomb ruler is very different from your run-of-the-mill tape measure. These strange rulers are defined in terms of constraints, and are “optimized” when they are the shortest they can be. While not ...