Information Density

In Japan you often see small two dimensional bar codes that cellphone cameras can decode as a web address. They are normally about a cm square, and are often found on the bottom of advertisements and occasionally on the business cards of certain Japanese companies that want to seem tech savy.

Last week I came across this somewhat larger than usual example, about 16square meters... which to store a single web address seems like overkill. Interestingly no text, so the only way to know what it was advertising was to scan it.