Matter is traditionally classified into three main phases: solid, liquid, and gas, with plasma recognized as a fourth state. Discussions highlight the complexity of classifying states of matter, noting that some substances, like ice, can exist in multiple phases simultaneously. The conversation also touches on advanced states such as Bose-Einstein condensates and neutron star matter, suggesting there may be more than four states. The surface properties of solids introduce additional complexity, as they can behave differently than their bulk counterparts. Overall, the classification of matter is a nuanced topic that reflects both scientific understanding and the limitations of existing frameworks.