How does mass/bulk flow substances is different from diffusion?

Differences between mass flow and diffusion are

Mass Flow :
It is the movement of substances in bulk or in masses from one point to another due to pressure differences between the two points.
All substances dissolved or suspended in water, move with the sarthe pace.

Diffusion :
It is the movement of substances from a region of higher concentration/pressure to a region of lower concentration or pressure.
Different substances move independently depending on their concentration gradients.