Answer:
In a metallic substance, electrons are shared among all of the metal atoms in the sample, forming a "sea" of electrons that surrounds the metal ions. This electron sea is responsible for many of the unique properties of metals, including their high conductivity, malleability, and ductility.
The electron sea in a metallic substance allows the metal ions to slide past one another easily, making it easier to deform the metal without breaking it. In contrast, ionic and covalent compounds are held together by strong chemical bonds, which makes it more difficult to deform these materials without breaking the bonds. This is why metals are generally more malleable and ductile than ionic and covalent compounds.