Hi kiddo! Do you know what a ring is? No, not like a ring that you wear on your finger. In math, a ring is a special type of structure that has two operations called addition and multiplication.
Now, a discrete valuation ring (DVR, for short) is a special type of ring that has a few really important properties. One is that it has a unique element called a "valuation." This valuation is like a special way of measuring the size of elements in the ring. Think of it like when you compare two pieces of candy - you might say that one is bigger than the other. In the same way, the valuation of an element tells you how "big" it is in the ring.
Another important property of a DVR is that it's "discrete." This means that the elements in the ring are nicely spaced out, almost like they're on a ladder with each rung just one step apart. This makes it easy to compare elements and see which one is bigger or smaller.
Lastly, a DVR is a "ring," so it still has all the usual addition and multiplication rules. But because it has a valuation, it also has a new and special way of measuring the size of elements.
So that's pretty much it - a discrete valuation ring is a special type of ring that has a unique way of measuring the size of its elements and is really good at comparing elements with each other.