For a country with many rigid social rules and etiquettes, Japan has a whimsical way of communicating public service announcements to its public, as to be expected in a country which is obsessed with cute and quirky designs and prints spliced with the emphasis on politeness and being careful not to cause offense.
It is hard to find signs in Japan one would expect in most other countries with their glaring colours and blaring messages. Instead imagine teddy bears in posters against public drunkenness, or this poetic poster against taking up too much seat space on the train:
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"If you're going to read words during rush hour, we wish you'd also read between the lines" and "A person was waving at me, he was waving away my smoke"
After the Fukushima nuclear accident there has been a massive public movement for energy conservation. Some Japanese graphic artists have made their own posters for this cause and many are in the same vein as those typically cute yet effective PSA posters.