OnResize vs OnSizeChanged

Answer from Bob Powell [MVP] found on internet (discussion goes further) :

Internally, OnSizeChanged calls OnResize so they are pretty tightly linked.

The OnResize method is responsible for invalidating the control if the ResizeRedraw style is set.

AFAIK, the Resize-Event is fired if the actual size of the form changes. The SizeChanged-Event fires if the value of the Size-Property is updated.