Facilitated diffusion:

Many molecules do not diffuse freely across cell membranes because of their size and charge. Such molecules are taken into or out of the cells with the help of transport proteins present in cell membranes.

When one of these transport proteins makes it possible for a substance to move down its concentration gradient (from higher to lower concentration) the process is called facilitated diffusion. The rate of facilitated diffusion is higher than simple diffusion.

Facilitated diffusion is a type of Passive transport:

Facilitated diffusion is also a type of Passive transport because there is no expenditure of energy in this process.