What characteristic distinguishes stainless steel from regular steel?

Stainless steel is distinguished from regular steel primarily by its improved corrosion resistance. This crucial characteristic arises from the addition of chromium, which forms a passive layer of chromium oxide on the surface of the steel. This layer acts as a protective barrier against environmental factors such as moisture and oxygen, reducing the likelihood of rust and corrosion that typically affect regular steel over time.

While regular steel is prone to oxidization and rusting when exposed to moisture, stainless steel's resistance to corrosion makes it ideal for various applications, especially in environments where there is high exposure to water or chemicals. This is essential for industries such as food processing, healthcare, and construction, where cleanliness and durability are paramount.

The other options, while relevant in their own contexts, do not capture this fundamental property that defines stainless steel and its applications compared to regular steel.