Isomorphism is a concept in mathematics and science that describes a relationship between two structures that are fundamentally the same in form or function, even if they appear different. For example, in group theory, two groups are isomorphic if there is a one-to-one correspondence between their elements that preserves the group operation. This means that the groups behave identically in terms of their algebraic properties. In graph theory, isomorphism refers to a situation where two graphs can be transformed into each other by rearranging their vertices. If there is a way to match the vertices of one graph to the vertices of another while keeping the connections (edges) intact, the two graphs are considered isomorphic. This concept helps in understanding the underlying similarities between different mathematical structures.