A serrated

Serration

Serration generally refers to a saw-like appearance or a row of sharp or tooth-like projections. A serrated cutting edge has many small points of contact with the material being cut. By having less contact area than a smooth blade or other edge, the applied force at each point of contact is...

 blade is a type of blade

Blade

A blade is that portion of a tool, weapon, or machine with a cutting edge and/or a pointed tip that is designed to cut and/or puncture, stab, slash, chop, slice, thrust, or scrape animate or inanimate surfaces or materials...

 used on saw

Saw

A saw is a tool that uses a hard blade or wire with an abrasive edge to cut through softer materials. The cutting edge of a saw is either a serrated blade or an abrasive...

s and on some knives

Knife

A knife is a cutting tool with an exposed cutting edge or blade, hand-held or otherwise, with or without a handle. Knives were used at least two-and-a-half million years ago, as evidenced by the Oldowan tools...

 or scissors

Scissors

Scissors are hand-operated cutting instruments. They consist of a pair of metal blades pivoted so that the sharpened edges slide against each other when the handles opposite to the pivot are closed. Scissors are used for cutting various thin materials, such as paper, cardboard, metal foil, thin...

. It is also known as a dentated, sawtooth, or toothed blade.

A serrated blade has a cutting edge that has many small points of contact with the material being cut. By having less contact area than a smooth blade, the applied force at each point of contact is relatively greater and the points of contact are at a sharper angle to the material being cut. This causes a cutting action that involves many small splits in the surface of the material being cut, which cumulatively serve to cut the material along the line of the blade.

Cuts made with a serrated blade are typically less smooth and precise than cuts made with a smooth blade. Serrated blades can be more difficult to sharpen using a whetstone

Sharpening stone

Sharpening stones, water stones or whetstones are used to grind and hone the edges of steel tools and implements. Examples of items that may be sharpened with a sharpening stone include scissors, scythes, knives, razors and tools such as chisels, hand scrapers and plane blades...

or rotary sharpener than a non-serrated, however, they can be easily sharpened with a diamond sharpening rod. Serrated blades tend to stay sharper longer than a similar straight edged blade. A serrated blade has a faster cut but a plain edge has a more clean cut.