Witt group

Okay, so let's imagine you have a group of different animals like lions, elephants, hippos and giraffes. But instead of just looking at them, you want to study them in a special way.

That's where a Witt group comes in. It's like a special group of animals, but instead of lions and giraffes, we have mathematical objects called "vector spaces." These are kind of like boxes that we can put numbers in, and do some special math with them.

But we don't just want to study one box at a time. We want to look at a bunch of different boxes and see how they're related to each other in a special way. That's what a Witt group does - it helps us understand how different vector spaces are connected to each other.

It's kind of like a puzzle, where we take all the vector spaces we're interested in and try to fit them together in the right way. By doing this, we can learn new things about math and how things fit together, just like you might learn new things about animals by studying them in a group.