DEAD LETTERS: A boom in Internet shopping is helping keep alive moribund postal services across the developed world. But the core of their business — letters — is declining precipitously, and data from many countries indicate that parcels alone won't be enough to save them.

CUTTING BACK: The once-proud postal services that helped build modern society are scaling back operations, risking further declines.

WHAT THEY'RE DOING: The United Kingdom is preparing to wash its hands of mail deliveries entirely by selling the Royal Mail. The U.S. Postal Service sparked uproar this month when it announced plans to stop delivering letters on Saturdays. New Zealand is considering going to three days a week.