Can a margin affect on total size of width and height?

Question

All I know is that margin is a space around the box and padding is a space inside the box
But here I saw something different?
I saw the margin affected the width of a box
Can someone explain it to me?
I got confused

Answer 1

where did you see it?

Answer 2

I saw here in solo learn in CSS box model section

Answer 3

coal hi,
You can make some simple tests with the developper tools of your browser by inspecting elements...
Even try differents browsers as they can have differents default setting for elements.

Answer 4

You might find answers here:

https://medium.com/launch-school/https-medium-com-dembasiby-understanding-the-css-box-model-b005a82593a6#:~:text=It%20is%20important%20to%20note,bottom%2C%20and%20margin-left.

https://stackoverflow.com/questions/36098920/do-we-include-margin-in-css-box-model-while-determining-width-or-height-of-a-ele