Hotel Key Cards

Aaron Rasmussen explains how hotel key cards work, and how best to secure them against misuse or malicious duplication.

-DD

Why Five Fingers and Toes

Michael Coates explains why most creatures have five digits as fingers and toes.

-DD

Underwater Brine Pools

Kaushik Patowary writes about underwater brine pools . Unless the hot brine and methane found in these pools is continually refreshed from the rocks below, the brine would dissapate and the unique environment would perish.

-DD