Sympathetic magic is a belief system where objects or actions can influence one another based on their similarities or connections. This practice often involves using a representation of a person or object, such as a voodoo doll, to affect the real counterpart. The idea is that by manipulating the representation, one can bring about changes in the actual entity. There are two main types of sympathetic magic: homeopathic magic, which operates on the principle of "like affects like," and contagious magic, which relies on the belief that once two things have been in contact, they remain connected. These practices have been observed in various cultures throughout history.