Okay kiddo, so you know how big cities like Rome have a lot of hills and neighborhoods? Well, one of those neighborhoods in Rome is called "Esquiline." It's kind of like a big chunk of the city that has its own history and culture.
Esquiline used to be just outside of the old city walls, but as Rome grew and grew it got swallowed up into the city. Nowadays, Esquiline is actually one of the biggest neighborhoods in Rome, with lots of different kinds of people living there.
There are also a lot of cool things to see in Esquiline, like ancient ruins and beautiful churches. In fact, some of the most famous landmarks in Rome, like the Colosseum, are actually in or near Esquiline!
So basically, Esquiline is just a really interesting and important part of the big city of Rome.