What is the difference between volume and density?

Answer 1

Simply: Volume (V) is how much space an object takes up whereas density is how "compressed" an objects mass (m) is. Density = m/V

Example:

Imagine a ton of feathers and a ton of iron.

They both have the same mass (weight) but they have different volumes and density.

Answer 2

Volume is a quantity which represents the size of an object, its dimensions are length3. Imagine a cube, like a dice but bigger, with all sides equal to one foot. The area of any face is one square foot, and the volume is one cubic foot. Of course the object could be any solid shape, and it would have a volume in cubic feet, or whatever unit you are using, but it would not be so easy to determine the volume. Regular objects like spheres have formulas for their volume, but for complicated shapes the best way to find the volume would be to immerse the object in water in a measuring cylinder and note the change in water level.

Density just means mass per unit volume. You can express this as pounds per cubic foot, grams per cubic centimeter, or whatever units you like.

Specific density is often quoted as well, this means density relative to water, which is taken as unity. Thus the specific density of a substance is how much heavier or lighter it is relative to water.