ELI5: Explain Like I'm 5

Image (category theory)

Okay kiddo, so let's talk about images in category theory!

Imagine you have a bunch of animals - cats, dogs, and birds - and you want to group them together based on certain criteria, like the color of their fur or how big they are. That's kind of like what images do in category theory.

An image is a way of grouping together elements in a category based on a certain property or relationship. So just like you might group together all the animals with black fur, an image in category theory might group together all the elements that have a certain property or satisfy a particular relationship.

Here's a more technical definition: given a morphism (which is like a fancy way of talking about a relationship between two elements in a category), the image of that morphism is the smallest sub-object of the target object that includes the image of the morphism.

Okay, but what does that actually mean? Well, think of it this way. If you have a morphism going from object A to object B, you can imagine drawing an arrow from A to B to show the direction of the relationship. The image of that morphism would be like drawing a box around all the elements in B that are connected to by that arrow (and any other arrows that start at A and end in that box). It's the smallest box you can draw that includes all those elements.

Does that make sense, kiddo? Images are like the boxes that group together elements with a particular relationship or property, just like you might group together all the animals with black fur.
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