Every country has its own set of rules or laws.
Laws are created by governments, and they are generally approved by a legislative body such as the Congress or the Parliament. Laws are typically made for a reason, but some laws can be really silly.
It was once against the law to slam a car door in Switzerland. And Donald Duck comics were banned in Finland because the cartoon character didn't wear pants. In England, if you found a whale on the beach, you couldn't keep it. It belonged to the king because it was considered a special animal.