Pull any bill out of your wallet. See the dark green numbers on the top-left and top-right corners? Those are serial numbers, and some are more rare than others. If you happen to have paper money with ...

Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. A paper wallet is a piece of paper with your ...

To make light-weight, inexpensive electronics using renewable materials, scientists have turned to a technology that is almost 2,000 years old: paper. In an important step toward paper-based devices, ...