Final answer:
Metallic bonds are formed by metals, and they exhibit unique properties such as high thermal and electrical conductivity, metallic luster, and malleability.
Step-by-step explanation:
Metallic bonds are formed by metals. In a metallic bond, each metal atom is bonded to several neighboring atoms, and the bonding electrons are free to move throughout the 3-dimensional structure. This creates a sea of delocalized electrons around the metal atoms, which gives rise to many useful properties of metals, such as high thermal and electrical conductivity, metallic luster, and malleability.