ELI5: Explain Like I'm 5

street running train

Okay kiddo, you know how you sometimes see trains going down the tracks like Big Bird or Thomas the Tank Engine when you're out driving in the car? Well, sometimes those trains don't have their own special place to go, so they have to go on the same roads that cars and trucks use. That means the train will be on the same street as you!

Since a train is a really big and heavy machine, people need to be extra careful when it's on the street with them. That's why the train will go really, really slow - almost like a snail - and it might even have someone walking in front of it to make sure everything is safe.

When the train needs to cross over another road or intersection, it will honk its horn to let everyone know it's coming. And just like you always look both ways before crossing the street, cars and people need to do the same when a street-running train is around.

It might seem pretty strange at first, but street-running trains have been around for a long time and they help move things around the city so everyone can get what they need. Plus, it can be pretty cool seeing a train come down the street like it's on a big adventure!
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