iso paper sizes
this is a great conversation to have in a pub. did you know that AO size paper has an area of 1 square metre and that this allows you to work out the weight of a document
markus kohn explains it all here. it then goes on to effect the size of everything from filing cabinets to credit cards. the british complied with european standards a while ago but the americans are still suffering from their incompatibility with the rest of the world
and for my own information the square root of 2 is 1.4142