Knife: Tool with a cutting edge or blade

The plural form of "knife" is "knives." Knives can serve various purposes. Hunters use a hunting knife, soldiers use the combat knife, scouts, campers, and hikers carry a pocketknife; there are kitchen knives for preparing foods, table knives, weapons, knives for throwing or juggling, and knives for religious ceremony or display.

Archaeologists have discovered sharp-edged tools as ancient as 2.6 million years old. Sharp stone tools became more advanced in design during the late Lithic periods, and a variety of techniques was used to produce such ‘knives’ in the Neolithic era. The copper and bronze ages followed, and of course brought tremendous changes to the ‘sharp-edge’ technology. These new metal tools were much more durable than stone ones, and hence mining and metal-processing became an important activity.

• Cooking or kitchen knives, also known as the chef's knife. Several types of knives are used in cooking. Kitchen knives are sharp knives with wood or plastic handles used for chopping food and meat that is going to be cooked.
• Table knives: These knives are used to cut up food for eating. Some table knives are sharper than others, but none are as sharp as kitchen knives. Steak knives are sharper because they need to cut steak. Fish knives and butter knives are also used at the table and have rounded blades that are not sharp.
• Hunting knives are used for skinning animals.
• Fishing knives are used for cutting open fish.
• Construction knives and utility knives are used for cutting vinyl flooring, insulation, plastic sheathing, and carpet.
• Pocket knives These knives are used often.
• Butter knife A knife used to cut butter or spread things. Some people use it illegally to kill people.
• Paring Knife paring knife is ideal for making garnishes and peeling vegetables and fruit.
• Boning Knife helps to take meat apart from bone.
• Carving Knife is ideal for carving large whole poultry pieces.

There are many kinds of knives, depending on what is to be cut. With the right knife, the cuts you want to make will happen faster and more easily. With the wrong kind of knife, it will take more effort to perform the same amount of work. When a knife is too small to cut something, a saw, axe, or power tool may be needed.

Carrying knives is illegal in many countries, especially if the blade is longer than several inches. Another type of knife which is illegal in many places is the "switchblade," a knife that has a button which when pressed activates a spring to open the knife.

• Scissors
• Guillotine
• Saw