Other meanings of Knife
Tools & Weapons
A knife is a tool or weapon with a cutting edge or blade, typically attached to a handle. Knives have been essential to human survival for over two million years, evolving from simple stone flakes to precision-engineered instruments used in cooking, combat, surgery, and countless crafts.
The knife is among humanity's oldest tools, with stone flakes dating to about 2.6 million years ago in Ethiopia, associated with Homo habilis and the Oldowan industry.1 These early cutting tools were simple sharp-edged stones, later refined into hand axes and flaked blades. The advent of metalworking around 5000 BC introduced copper knives, followed by bronze and iron, which allowed for sharper, more durable edges and more varied designs.2 By the Iron Age, knives were common across Europe, Asia, and Africa, serving as both tools and weapons. The development of the folding knife is attributed to the Romans around the 1st century AD, primarily for use by soldiers and travelers.3 The Industrial Revolution brought mass production, making knives affordable and ubiquitous, while modern metallurgy and ergonomics have led to specialized designs for nearly every conceivable task.
A knife consists of a blade and a handle, with the blade's geometry determining its function. Blade shapes include drop-point, clip-point, tanto, and spear-point, each optimized for tasks like piercing, slicing, or utility work.4 Common blade materials include stainless steel, carbon steel, and high-alloy tool steels, each offering trade-offs between edge retention, corrosion resistance, and ease of sharpening. Ceramic blades, introduced in the 1980s, are extremely hard and wear-resistant but brittle.5 Handles are made from wood, bone, plastic, rubber, or composites, with ergonomic designs to reduce fatigue and improve grip. The tang—the extension of the blade into the handle—affects balance and strength; full-tang knives are generally more durable. Locking mechanisms in folding knives, such as liner locks, frame locks, and back locks, ensure safety during use.
Knives are categorized by their primary use. Kitchen knives include chef's knives, paring knives, and bread knives, each designed for specific cutting tasks.6 Hunting and outdoor knives, such as Bowie knives and survival knives, are built for field dressing, woodcraft, and self-defense. Combat knives, like the Fairbairn–Sykes fighting knife, are designed for military use. Pocket knives and multi-tools, such as the Swiss Army Knife, are everyday carry items. Surgical scalpels are precision knives used in medicine, while craft knives (e.g., X-Acto) are used for cutting paper and other materials. Specialized knives include diving knives, throwing knives, and ceremonial knives like the kris or kirpan. The design of each type reflects its intended environment, from corrosion-resistant blades for marine use to insulated handles for electrical work.
Beyond common uses, knives have niche and surprising roles. The uluri, a small knife used by the Suruwaha people of the Amazon, is traditionally used for infanticide and suicide, reflecting cultural practices that are now controversial. In forensic science, knife wound analysis can reveal details about the weapon's shape and the force used. The kukri, the national knife of Nepal, is both a tool and a weapon, and its curved shape is said to be based on the talon of a mythical bird. The balisong, or butterfly knife, is a folding knife that originated in the Philippines and is now a focus of flipping as a sport. Knife throwing, once a practical skill, is now a competitive art. The kirpan, a ceremonial dagger worn by Sikhs, is a religious article of faith, and its legal status has been debated in several countries. Additionally, the switchblade, once vilified in popular culture, has seen legal restrictions relaxed in many jurisdictions in recent decades.
Knife laws vary widely by country and region; always check local regulations before carrying or using a knife.
Help improve the encyclopedia. Reports go straight to the site manager.