What Does Density Mean?

I still do not get the flaming thing so help me on my geography homework now

Density is a term that refers to a measure of mass per volume. The symbol of density is "ρ". It is a Greek symbol. Its SI unit is the kilogram per cubic meter or kg/m3. The average density of an object is calculated by dividing the total volume of the object with its total mass. Volume has an inverse relationship with density. Therefore an object with greater density would have less volume and the object with less density would have greater volume. Iron and water are examples of this fact.

Thus the formula to find out the density of an object is p = m/v where p is the objects density, m is the object's total mass and v is the object's total volume. The density of a liquid is measured with the help of a device called pycnometer and a gas pycnometer is used to measure the density of solids.

It is part of a measuring it is learned in grade 8.

Mass per unit volume of substance

Usually it's like the thikness of a substance. I think

Density means how tightly the particles are packed in a certain solid liquid or gas.