What is energy, is it matter or just a number to explain minerals and matter

Does a wood board have energy or is it just matter?

Everything has energy. The only way to eliminate all energy is to reduce the temperature to -270°F or 0° Kelvin. This is called absolute zero. This is the only temperature in which the atoms in any material or energy ceased to vibrate. Energy and matter are essentially interchangeable. Matter, according to physics is just very dense energy.

I wouldn't say that energy is matter, more that matter is just energy - wood boards included. :)
(E=mc^2 is all about how matter and energy relate to each other.)