Kniv

Kniv, or knife, is a handheld bladed tool used for cutting, slicing, and piercing. The term kniv is cognate with the English knife and the Danish kniv, tracing to Old Norse knífr and earlier Proto-Germanic roots. Knives have a long history, evolving from stone blades in prehistoric times to metal blades in modern use.

Most knives consist of a blade attached to a handle. Blades are manufactured from steel (carbon, stainless) or ceramic, with a variety of edge hardness achieved through heat treatment and tempering. Common designs include fixed-blade knives, where the blade is permanently connected to the handle, and folding knives, in which the blade folds into the handle for safety and portability. Blade shapes range from straight and chisel-like to curved and spear-point forms.

Knives serve diverse purposes. In the kitchen, standard types include the chef's knife, paring knife, utility knife, and serrated bread knife. Outdoor and hunting knives are built for field use and durability, while utility blades are used for everyday tasks. Some knives are specialized for ceremonial, testing, or rescue work.

Care and maintenance affect performance and safety. Regular sharpening or honing keeps edges acute, while proper cleaning and drying prevent corrosion. Knives should be stored securely and used on appropriate cutting surfaces to avoid damage.

Legal and cultural considerations vary by country and region. Some jurisdictions regulate blade length, carrying in public, or the sale of certain knife types. The use of knives in accordance with local laws and safety guidelines is advised.