Stainless steel is strong, durable, and resistant to corrosion, but less flexible that many other metals.
Stainless steel has been implemented in many industries relevant to survival gear due to its durability and low cost.
For cookware, stainless is very popular. It is cheap, well tested, and doesn't leach chemicals into food.
It is used in the manufacture of many tools
Stainless is probably the most common material for producing knives due to its reasonable ability to hold an edge and resistance to rust when compared to carbon steel. Many individuals prefer carbon steel, however, for its greater flexibility and ability to hold an edge.
Stainless steel is used with many firearms due to the same resistance to corrosion that makes it desirable for other products. Particularly where the firearm may be exposed to salts such as on board boats at sea or when carrying close to the body (concealed carry). For this reason the primary stainless steel firearms are pistols though there are some shotguns and rifles that are available in stainless steel. One downside of stainless steel weapons is their greater visibility, due to its being a white metal; this can be mitigated through coatings and wraps.