Eurotunnel
In short
The Eurotunnel is the undersea rail link connecting Folkestone in the United Kingdom to Coquelles in France. It is managed by the company Getlink.
In plain words
It is a long tunnel under the sea that lets trains travel between Britain and mainland Europe. People use it to drive cars on special shuttles or to take high-speed passenger trains.
A simple example
A driver can park their car on a LeShuttle train in Kent and drive off in France twenty minutes later.
Why it matters
It provides a vital transport link that avoids the long ferry journeys across the English Channel. This makes moving goods and people between the UK and Europe much faster.
Easy to mix up
Do not confuse the Eurotunnel with the Channel Tunnel, which is the physical structure itself.