ELI5: Explain Like I'm 5

Free group

Okay, kiddo, imagine you have a bunch of balls that you can play with. Some of these balls are colored red and some are colored blue. Now, if you want to group these balls together, you can do it in different ways. You can put all the blue balls in one group and all the red balls in another, right?

Well, in mathematics, we have something called a free group. It's a group of things that we group together without any specific order or relation between them. So, just like the balls, we can take a bunch of letters and group them together to form a free group.

Let's say we have the letters A, B, and C. We can group them together to form a free group, which we write as {A, B, C}. This means that we can use any of these letters to form different combinations, kind of like when we mix and match our toy blocks.

Now, one important thing about a free group is that there are some rules we have to follow when we start combining the letters. We call these rules the group's axioms. They are like the instructions that tell us how to play with our toys safely.

For example, one of the axioms for a free group is that we can't do the same thing twice. So, if we have the combination AB, we can't add AB again to get AABB, because that's not allowed in a free group.

Another rule is that we can shuffle the order of our letters, but we can't add or take away any letters. For example, if we have the combination ABC, we can shuffle it to get BCA or CAB, but we can't add any more letters or take any away.

So, that's basically what a free group is in mathematics. It's a group of things that we can combine freely, but with some rules we have to follow to make sure we're doing it right.