Explain intravascular fluid compartment - extracellular fluid?

The extracellular fluid compartment is sub-divided into the intravascular fluid compartment (fluid within the blood vessel) and intercellular/interstitial/ extravascular fluid compartment (fluid between the body cells but outside of the blood vessel).

The intravascular fluid comprises of all the fluid within the blood vessels of the "vascular" system - namely, the arteries, veins and capillaries. The intercellular compartment, on the other hand, contains the fluid around and between the cells of the body, which carries nutrients to the cells and collects waste products for eventual excretion.

The intravascular fluid is separated from the intercellular fluid by the walls of the blood vessels, which also form a semipermeable barrier that allows the water to pass through it but exerts a strict selective control over the passage of other chemicals.