1) a popular soda that got its name from the drug that was put in it when it was first made: cocaine. Nowadays, the soda has no drugs in it, so any one can safely drink it. Is apparently at "competition" with pepsi, but both are pretty much the same.
2) short for cocaine 3) a fuel/type of carbon
1) customer-"may i have some coke?"
waiter-"we don't have any. how about pepsi?"
2) coke is commonly used in drug-dealing
3) my car ran effeciently off that coke