Springfield is a particularly common toponym in the English language, especially in the United States.
A toponym by the way, is a placename, particularly one named after a geographical feature. They’re quite common in all languages, and some English-language toponyms are translations of quite literal names in other languages.
Springfield isn’t too hard to figure out. It probably first originated to refer to communities which featured fields next to springs. As it’s quite advantageous to have a spring next to your fields, for irrigation and drinking water, a lot of people planted crops near springs, hence there being so many Springfields.
The most famous Springfield of course, is the one in which the Simpsons live. Unsurprisingly, the name was chosen for the town because it’s so common, to make it feel like a typical American town. Which is why it’s occasionally annoying to see so many articles about which town might be the “real” Springfield, and in which state it might be located (spoiler alert: The Simpsons is a work of fiction, and therefore doesn’t have to be located in a real state).
It’s undoubtedly confusing to have so many towns with the same name (and there are other common toponyms such as Newcastle, Casteltown, Newport etc.). That of course wouldn’t have been a probably when these names first came about, which is why thinking about them is such an interesting glimpse into the past. First of all, these names developed quite naturally, through consensus, and were generally quite descriptive, making it easy to know where they referred to. Secondly, people weren’t considering vast stretches of land when referring to local placenames. It was therefore OK to call your local area Springfield, because there wasn’t anywhere within travelling distance with the same name.
Of course once transport helped people to travel farther, people realised that lots of places had the same name, but the names had stuck by then. But while it might be confusing, it’s generally not much of a problem. Unless you’re once of those people who gets a flight from the wrong Birmingham…