Okay kiddo, imagine going to a restaurant or a cafe and you see people drinking hot brown liquid from small cups. That's coffee! Coffee service is when someone brings coffee to people who want to drink it.
Usually, there are special people called baristas who are trained to make coffee. They use a machine called an espresso machine to brew the coffee. They put fresh coffee grounds into a small container called a portafilter and tamp it down. Then, they press a button or a lever to make hot water go through the grounds and into a cup.
Once the coffee is ready, a barista can add milk, sugar or syrup to make it taste different. Then, they carry the coffee to where people are sitting and serve them.
Coffee service can also include things like brewing a big pot of coffee and leaving it on a table for people to serve themselves. Or, having a mobile coffee cart or truck that can go to different places and serve coffee on the go.
Overall, coffee service is all about making sure that people who want to drink coffee have a good experience and get the caffeine they need to start their day!