The telephone numbers you must check
These two telephone number are emergency calls in Japan.
One is for calling police, the other one is for fire.
It helps you and people around you; just two 3-digit numbers.
It is important to tell them where you are. You may find another post how to identify where you are by checking mailing box or vending machine.
Anyway, it is good idea that always you check the address you are anytime.