Understanding ISO 216: The Logic Behind Standard Paper Sizes

https://wiki-wire.win/index.php/Understanding_ISO_216:_The_Logic_Behind_Standard_Paper_Sizes

Ever wonder why A4 paper feels just right? ISO 216's clever logic uses a consistent aspect ratio, so folding or scaling an A4 down to A5 keeps proportions perfect. This neat system, based on the square root of two, makes printing, cutting, and stapling documents surprisingly efficient worldwide.