Fertile window? What?!?!

Question

What on Earth is a fertile window, like explained in the simplest way possible. My school never talked about it and I’ve never heard about it until now. 
On the side note: They should really teach MORE about this stuff. 
Any help is good, I’m just concerned about it.

Answer

It’s the easiest time of the month to get pregnant. It’s called ovulation when the egg is released from the ovary to be fertilized. But remember this is just an app and is just an estimate. In reality you could be ovulating at a different time.

Answer

Basically it's the week of your menstrual cycle that it is the most likely you can get pregnant. It doesn't mean you will or won't.

Answer

Ovulation