InterRail started as the name of a train pass that lets you ride many trains across a lot of European countries on one ticket, often for a set number of days. Young people, especially, used it for a long summer trip from country to country. People also use it as a verb: to InterRail, or ‘go interrailing’, meaning to travel around Europe on that kind of pass. It is a brand-like name, so we keep the capital R in the pass name. Though actually, there is a sister ticket called Eurail. In simple terms, InterRail has long been the pass for people who already live in Europe; visitors from outside Europe more often buy Eurail. A student in Taiwan planning that trip should check which pass they can use, not just copy a European friend’s word. It is also not any old train ticket — it is this special many-country pass (and the trip you take with it).