Metallic structure
Regular lattice arrangement of positive ions surrounded by a sea of delocalized electrons
Metallic bonding
The electrostatic attraction between the positive ions in the lattice and the delocalized electrons
Alloy
Homogeneous mixtures of two or more metals, or of a metal with a non-metal
Why are metals malleable/ductile?
Bonding is non-directional, so when layers slide over each other the structure is the same unlike ionic solids where like charges repel