General

I can't speak for other countries. But in the US, Pittsbugh and west is pop, east of that, it's soda.

Coke, and other companies try very hard to save their trademarks. If someone from Coke orders a Coke, and you get a Pepsi, the restaurant will probably be sued by Coke. There are other words that people do not realize is a trademark for a particular manufacturer. That includes Ping Pong, Yoyo, and Formica.