Volume - The volume of any solid, liquid, plasma, vacuum or theoretical object is how much three-dimensional space it occupies, often quantified numerically. One-dimensional figures (such as lines) and two-dimensional shapes such as square geometry squares are assigned zero volume in the three-dimensional space. Volume is commonly presented in units such as mililitres or cm3 (milliliters or cubic centimeters).
Volumes of some simple shapes, such as regular, straight-edged and circular shapes can be easily calculated using arithmetic formulas. More complicated shapes can be calculated by integral calculus if a formula exists for its boundary. The volume of any shape can be determined by displacement. In differential geometry, volume is expressed by means of the volume form, and is an important global Riemannian invariant. Volume is a fundamental parameter in thermodynamics and it is conjugate to pressure.