Coke is the Bigger Established
US Cola Company, it looks
kinda' like Japan's Flag?
Yin and Yang may be a foreign concept for American people over the age of 50, perhaps the best way older Americans can relate this contradictory concept of balance, harmony, tension, and rivalry is to think of the Korean War. If you ever study the Korean War, it is dynamically like Yin-Yang energy flow.
The circular icon on the Korean Flag is essentially the Yin-Yang symbol, minus the contradictory dots. This symbol originally came from China. It is the icon for the philosophy-religion of Taoism.
The Yin-Yang symbol. A Korean War Veteran told me his troop called it the 'meatball' and the US Gov didn't bother to explain what it meant or what it was other than that it was the South Korean Flag. Simply put the Yin-Yang symbol is a reflection of the inherent dichotomy to any idea, choice, or stance one must take, " To do or not to do." Do you buy Coke or Pepsi? Sure there are other choices out there, but restaurants who want to get 'corporate game' must choose a side 'Do we serve Coke or Pepsi?' Otherwise you'll just stay in the minor leagues with RC Cola and Shasta.
In 1992 Crystal Pepsitripped people out, did you save your
Crystal Pepsi Bottles? 
Back in the 80s and 90s the logo of Pepsi looked a lot like the flag of South Korea. Pepsi's icon caused media stir in South Korea and was subsequently changed. Coincidentally the colours of Coke mirror the flag of Japan.
Korea and Japan are natural rivals just as much as Coke and Pepsi are rivals. Do you want to drive a Hyundai or Honda? If your are a minor league baseball player and want to play baseball in Asia you can choose to play in the pro-Korean or pro-Japanese league. Are you a recent college grad and want to expereince East Asia by teaching English in relatively safe, modern, well paying, non-communist, non Muslim nation? You must choose Japan or Korea.
In 1985 Coke switched the flavors
with New Coke, it made most Coke Drinkers mad,
but in the end it caused mad profits as via risky marketing tool
If you are having trouble wrapping your head around the Yin-Yang symbol just think of the natural and spontaneous rivalry and dynamic between Coke and Pepsi.
Both Coke and Pepsi are in the same market, as they are consumed in a similar fashion. Coke and Pepsi compete at fast food joints, movie theaters, and sports events (at home or at the stadium). People who drink cola can be choosy to non-choosy. I call the extreme Coke or Pepsi consumers
Cokanistas and
Contra-Pepsinistas.
Basically these people will flip out and refuse to drink the opposing cola if it served at a party or restaurant. On the other end there are non-aligned cola drinkers who really can't tell the difference or just don't care and drink whatever. Most people don't care but because of cola-extremists, restaurants must always confirm if Coke or Pepsi is okay when you ask for cola. I ask for the 'house-cola' or sometimes say, I'll have the 'Cokerpepsi.'
Personally I like them both. However my taste buds prefer Diet Pepsi over Diet Coke, but I wouldn't throw a hissy fit if a restaurant serves Diet Coke, I'd just drink it with a smile like Bill Cosby.
Pepsi is the relatively newer upstartUS Cola Company that provides 'choice'
Pepsi Changed Logo in 2008because it looked to much like Korean Flag Symbol
Classic Commercials featuring 80s Super Stars Bill Cosby and Van Halen stomping for New Coke and Crystal Pepsi.
In the Cosmic Contest for Cola Consumers the corporate universe is dominated by two factions: Coke and Pepsi.
Who lives at the bottom of the sea in a proverbial welcome mat for all to see?
