Okay, imagine a long string or a piece of rope that you hold in your hand. Now, if you twist it, you'll see a loop of twists on it, right? That's what we call a 't Hooft loop. It was named after a famous physicist Gerard 't Hooft, who discovered it.
Now, 't Hooft loop is a term used in physics to describe a special type of loop that we use to study how things behave in different conditions. Imagine you have a magnetic field (something that can pull objects made of iron towards it) passing around a loop of twisted rope or string. When you study the behavior of this arrangement, you can find out some interesting things about how the magnetic field interacts with the rope.
Scientists use 't Hooft loops as a way of describing how magnetic fields can affect things. It helps them to better understand how some materials react to magnetic fields, and how this can produce electric currents. They can also use it to describe how particles move in themselves.
So in simpler terms, a 't Hooft loop is like a twisted string, but when scientists study it, it can help them learn more about how things work in different conditions, like how magnetic fields impact objects.