Staples are U-shaped metal fasteners that are driven into a surface to hold or secure an object in place. Small staples are used with a stapler to attach pieces of paper together while larger staples might be used with a hammer or staple gun for fencing, masonry, roofing, and cardboard boxes. The legs of a staple can be allowed to protrude out the back side and folded over to provide greater binding than the friction of straight legs. A fastener is a hardware device that mechanically joins or affixes two or more objects together. It includes bolts, nuts, nail, pin and other such materials. Staples have some advantages over other metal fasteners. Staples are easier to produce, can be used to bridge between two materials butted together, and to provide a greater surface area than other comparable fasteners. Staples are manufactured in two styles. Staples include flat crown and rounded crown styles. Flat crown staples have flat top or crown and are used for general fastening. Rounded crown staples have a curved top and are used to secure wire, tubing, and other rounded items to flat surfaces. Staples are available in different sizes, lengths, styles, and materials.
The most common staples are used for paper. Staples are almost exclusively applied with a mechanical stapler which clinches the legs after they pass through the paper. Staples work when a force is applied to them. Modern staples for a paper stapler are made from bent wire and glued together to form a long strip of staples. The papers to be fastened are placed between the main body and the anvil. The papers are pinched between the body and the anvil then a drive blade pushes on the crown of the staple on the end of the staple strip. The staple breaks from the end of the strip and the legs of the staple are forced through the paper. Staples are manufactured from steel, aluminum, or stainless steel. Steel and aluminum staples are almost interchangeable and are used for most common applications. A stainless steel staple is more expensive, but it has high rust resistance. Staples can also be permanents fasteners in cases where once fastened it cannot be removed. A staple gun is a powerful hand-held machine used to drive heavy metal staples into wood or masonry. Staple guns may be driven by muscle power, electricity, or compressed air. Power staple guns can set staples at a somewhat faster rate than hand-powered models, but their main advantage is that they can be used continuously for hours with comparatively little fatigue. Staples are designed and manufactured to meet most industry specifications.
Staples are used in many applications. Saddle stitch staplers, also known as booklet staplers, feature a longer reach from the pivot point than general-purpose staplers and are used to bind pages into a booklet or signature. Saddle stitch staplers such as the Ring King can also use loop-staples that enable the user to integrate folded matter into ring books and binders. Staples also find use in medicine for the closing of incisions and wounds, a function also performed by sutures. Vertical Banded Gastroplasty (VBG), also known as stomach stapling, has been the most common restrictive operation for weight control. A special staple called stomach staple is used for stomach stapling. Ear stapling is used for weight loss, smoking, tension, and headaches. A small surgical stainless steel staple called an ear staple is strategically placed in the inner cartilage of the ear to target certain pressure points. Staples should adhere to standards specified by the International Standards Organization (ISO).