The Swiss Army Knife is a hand tool with a multitude of functions. This knife sports an array of various tools as well as a blade. They are known for having screwdrivers, can openers, scissors and more each stored away inside their own compartment within the handle of the knife. They are exposed through a pivot point action. The handle is usually red in color with a white cross (the emblem of Switzerland). The model used by the actual Swiss Army has an aluminum-plated handle.

This knife is synonymous with the pocketknife. It is often descriptive with a sort of tool, such as a software tool, that is a family of special-purpose tools.

There are various types and styles of Swiss Army knives each with its own tool combination for a specific tasks. The Swiss Army's knife has a corrugated metal surface with a red emblem and adorns a blade, a reamer, a bottle-opener/screwdriver/wire stripper, and a can-opener/screwdriver.

The simplest model sold includes a single blade. The most popular models typically include a combination of the tools included in the official army model, a second blade, tweezers, toothpick, corkscrew, Phillips screwdriver, nail file and scissors. Others include a saw, hook, magnifying glass, and ballpoint pen, fish scaler that doubles as a ruler, pliers/wire cutters and a key chain. The more recent features include USB flash storage, digital clock, digital altimeter, LED light, laser pointer and MP3 player. Whew!

A brass spacer on the official Army model allows the knife with the screwdriver and the reamer to be extended at the same time, to be used to assemble the Swiss Army assault rifles (the SIG 550 and the SIG 510).

A standard full-size SAK is approximately 3.5in long and .75in wide; smaller models are typically about 2.25in long and .5in wide. Thickness varies depending on the number of tools included. A flat version with somewhat fewer tools (but still retaining a knife) the size and shape of a credit card known as a Swiss Card, can be stored in a typical wallet. Although red SAKs are most common, black, blue, white, phosphorescent yellow, camouflage patterns, and other colors are available. The plastic cladding is usually opaque but may be transparent; metal- and wood-clad models are available.

Founded in 1884, since 1891 the company has delivered knives to the Swiss Army. The famous emblem, a cross in a shield, has been used by Victorinox since 1909. That year, the mother of founder Karl Elsener died the name of the company changed to "Victoria" in her honor. In 1921, with the introduction of "inox" (the French term for Stainless Steel) into their products, the brand and name of the company became the present Victorinox.

In 2005 Victorinox acquired Wenger, the other official supplier of the Swiss Army knife. Victorinox intends to keep both brands intact. Swiss Army knives are widely used outside the army. They are useful multifunctional instruments for everyday life and are available in a wide variety of sizes and functional combinations. Even NASA Astronauts have a Victorinox knife as standard equipment. Victorinox knives have also been taken to Mt. Everest and the Arctic. The flagship model of Victorinox, the Swiss Champ, is in the New York Museum of Modern Art's Permanent Design Collection.