Convenience stores sell canned coffee and self-service coffee from coffee machines. They also sell drip bags and other coffee machines, but for the convenience of being able to drink it on the spot, canned coffee or machine coffee are the best.
Canned coffee is excellent for long-term storage because it's stored in a can, which is why it's popular not only at convenience stores but also at mass retailers and vending machines.
Self-service coffee machines grind and brew the beans on the spot in a coffee maker, allowing you to enjoy a fresh aroma and flavor.