Presented is a mechanical switch that may include a first electrode; a second electrode spaced apart from the first electrode; a first material electrically connected to the first electrode; and a second material electrically connected to the first electrode. Any one of a hardness, a Young's modulus, a melting point and an insensitivity degree to external contamination of the second material is lower than any corresponding one of a hardness, a Young's modulus a melting point and an insensitivity degree to external contamination of the first material. When the first electrode and the second electrode are electrically connected to each other, after the first material is connected to the second electrode, the second material is connected to the second electrode.