States of Matter are the different forms taken by substances according to the kind of bonding presented by their elements and the physical form of the matter. Typically the four states of matter are the following
SOLID, is the state of matter characterized by resistance to deformation and changes of volume. In other words, it has high values both Young’s modulus and of shear modulus; this contrast e.g. with a liquid,which has a slow shear modulus.
LIQUID, where a fluid has its particles loose being free to form a distinct surface at the boundaries of its bulk material. The surface is a free surface where the liquid is not constrained by a container.
GAS, is the state in which matter expands to occupy whatever volume is available. Theoretically, in the perfect gaseous state matter has its particles working independently, with no interaction with other particles.