Looking again at the explainthatstuff.com QR code up above, we have: 1  Quiet zone: An empty white border that makes it possible to isolate the code from among other printed information (for example, on a dirty envelope, among the black and white print of a newspaper, or on smudged product packaging).
Valid units must be of the length type. âºâº Definition: Centimeter. A centimetre (American spelling centimeter, symbol cm) is a unit of length that is equal to one hundreth of a metre, the current SI base unit of length. A centimetre is part of a metric system. It is the base unit in the centimetre-gram-second system of units. A corresponding unit of area is the square centimetre.
Centimeter (British English: centimetre; abbr. cm) is a metric length unit, which is equal to 1/100 meter and 10 millimeters. Inch (abbr. in, symbol â) is a length unit in various systems. There are 12 inches in one foot and 36 inches in one yard. The international inch, accepted in the USA, equals to about 2.54 centimeters. The International System of Units (abbr. ISU, SI) is a modern system of measurement units, which is most widely used in the world.