In coordination chemistry, complexes can be categorized into two main types based on the nature of their ligands: homoleptic and heteroleptic complexes. A homoleptic complex is defined as one where a central metal atom or ion is surrounded by multiple ligand molecules or ions of the same type. For instance, [Co(NH3)6] represents a homoleptic complex where cobalt is bonded to six similar ammonia ligands. In contrast, a heteroleptic complex features a central metal ion coordinated to two or more different kinds of ligands. An example is [Co(NH3)4Cl2], where cobalt is bound to four ammonia molecules and two chloride ions. Grasping the differences between homoleptic and heteroleptic complexes is critical for understanding coordination chemistry, ligand types, and their implications in both theoretical and practical applications.