Cartesian Cordinate vs Unreal Cordinate System Why different?

Can Anybody explain to me why it is like this?

Or is there any settings I need to do

Also If you don’t believe me Just open Unreal and look at the viewport left bottom corner.

See if you adjust it like the left one you see in above image. Its really weird.

Found Something.

This seems enough

But, If anybody managed to explain it visually then it would be great though.

https://www.evl.uic.edu/ralph/508S98/coordinates.html

Can I switch to Right Handed System in Unreal? It makes more sense to me.

Can Anybody please explain to me what these people are saying?

https://forums.epicgames.com/udk/udk-development/level-design-and-creation/257550-change-to-right-handed-coordinates

Well, there is nothing we can do about it now.

I am starting to understood and getting used to it.

If anybody still struggling

watch this