language and communications

world : country codes and abbreviations

US & Canada : postal codes and abbreviations

environment and weather

Beaufort wind scale

wind chill temperatures

seawater salinity and constituents

seasonal variations in solar radiation

abundance of elements: Earth's crust and sea

abundance of elements: human body

particles and particle dispersoids

vapor pressure of ice and water

composition of air

measures and measurements

calendars:  2001   2002   2003   2004   2005

2006   2007   2008   2009   2010

2011   2012   2013   2014   2015

musical scales