The Heat capacity reference article from the English Wikipedia on 24-Jul-2004
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Heat capacity

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Heat capacity (abbreviated Cth or just C, also called thermal capacity) is the ability of matter to store heat. The heat capacity of a certain amount of matter is the quantity of heat required to raise its temperature by one degree. The SI unit for heat capacity is J/K (joule per kelvin).

Specific heat capacity

Main article: Specific heat capacity.

The 'Specific heat capacity' of a substance is the heat required to raise the temperature of one gram of it by one degree. Hence the heat capacity is the specific heat capacity multiplied by the mass.

Thermal capacitance

Heat capacity is related to thermal capacitance by the formula

or, more simply,

where
V = volume (m3)
ρ = density (kg/m3)
cp = specific heat (J/kgK) at constant pressure
m = mass (kg)

The product!!!!!! ρcp is known as volumetric heat capacity, thermal capacitance or (confusingly) thermal capacity, and has units of J/m3·K. Dulong and Petit predicted in 1818 that ρcp would be constant for all solids (the Dulong-Petit law). In fact, the quantity varies from about 1.2 to 4.5 J/m3K. For fluids it is in the range 1.3 to 1.9, and for gases it is a constant 0.001 J/m3K.