vba - Distinction between BackColor and ForeColor -

this more of conceptual question code issue. when coloring shapes vba, i've used forecolor property force of habit, curious how backcolor functions. documentation doesn't provide specificity distinction. pertinent information can see there is:

if set backcolor property on form object or picturebox control, text , graphics, including persistent graphics, erased. setting forecolor property doesn't affect graphics or print output drawn.

which doesn't seem adequately explain difference between them.

i did bit of experimentation setting , fore colors of shapes in different orders in code , different text , other items contained, cannot life of me find sort of consistent difference. frankly, seems backcolor property entirely useless, since forecolorhas seemed write on whatever color there is.

does know way explain difference between them (or source of better documentation can read on differences)?

backcolour used when apply twocolorgradient method.

for example, if select shape in powerpoint , type this:

?activewindow.selection.shaperange(1).fill.backcolor 

you'll see 16777215 (white) returned , if change red, you'll see no change:

activewindow.selection.shaperange(1).fill.backcolor.rgb = rgb(255,0,0) 

but if apply gradient method:

activewindow.selection.shaperange(1).fill.twocolorgradient _   msogradientdiagonalup, 1 

and change backcolor, you'll see change.