Cofibration

Ok, so imagine you're building with blocks. You have some big blocks and some small blocks. Now, you want to build a big tower with all your blocks. But, you can't just put the small blocks on top of the big blocks, because they might fall over. So, what you have to do is start with a big block and then add a small block to it, but you have to do it in a special way so it doesn't fall down. That's kind of like what a cofibration is.

In math, a cofibration is a special way of adding one set to another set. You have a big set and a small set, but you want to put them together in a way that they don't break apart. You have to do it in a special way, just like with the blocks. There are certain rules that you have to follow to make sure that everything stays together.

When you add the small set to the big set, you're creating something new. It's kind of like building a tower out of blocks. You're building a new structure that's different than what you started with. And, just like with the blocks, you have to be careful that everything stays in place.

Cofibration might seem tricky, but it's really just about adding things together in a way that makes sense and doesn't fall apart. So, next time you're building with blocks, remember that you're learning about cofibrations too!