Protein stability refers to the difference in Gibbs free energy, between its folded conformational state and extended states of a protein. Despite being small, this balance is crucial as it determines whether the protein remains in its native state or alters into a denatured state. A stable protein retains its functional state, which is important for its cellular processes and interactions with other molecules in cells. Factors which affect protein stability include temperature, oxidation, and hydrophobic interactions.