Wasting away material layer by layer due to the presence of air and moisture in the environment is termed corrosion.
Corrosion generally means the oxidation of metals.
For example: Rusting of iron
Corrosion changes the appearance of metals because of the oxide layer that forms on the surface. Like in the above example Iron when corrode changes to reddish-brown. Copper turns green, etc.
It also weakens the mechanical power of the metal over time.
Uniform corrosion:
The most frequent is corrosion, which occurs uniformly throughout metals.
This sort of corrosion is often defined as a chemical reaction that occurs consistently throughout the entire surface of the metal.
When a consistent attack occurs, the metal progressively thins down before failing.