margin-top
margin-bottom
Those are used to set paragraph and heading spacings.
Even for paper there are the heading and footer margins and the top and bottom margins and vertical margins for styles. Have a look at style editing in MS Word or LO Writer.
Also SOME ereader apps are not case sensitive, but most ereader HW is, so don't capitalise.
The padding is useful for things inside things, like a visible box or a table cell, where a margin might be less appropriate.
Though there is scope, where an inner thing without a stated property inherits the outer property. This can be obvious with <div> and <span> and less obvious with <body>.