Ginsu (/ˈɡɪnsuː/; pseudoword meant to evoke the idea of samurai heritage) is a brand of direct marketed knives. The brand is owned by the Douglas Quikut Division of Scott Fetzer, a Berkshire Hathaway Company. The brand was heavily promoted in the late 1970s and 1980s on U.S. television by using infomercials characterized by hawker and hard sell pitch techniques. The commercials generated sales of between two and three million Ginsu sets between 1978 and 1984.

Ginsu knives are an evolution of a product line developed by the Clyde Castings Company. The company filed for a trademark on the Quikut name for use on carving knives, butcher knives, fruit knives, kitchen knives and can openers in 1921.

Quikut knives were heavily advertised in the U.S. and Canada as inexpensive, stainless steel, hollow ground knives with a lifetime guarantee. Other well known brands that used Quikut knives as promotional items including Lipton Tea and Oxydol.

Large national newspaper, magazine and radio campaigns were used to market Quikut as far back as the 1930s. A 1938 campaign resulted in orders for 922,000 units. A 1939 campaign included a print ad on the back cover of the Saturday Evening Post.

In 1968, Quikut Corporation added spot television to their marketing effort and hired Cinécraft Productions, a sponsored film studio in Cleveland, to make a series of Quikut TV spots. In 1949 Cinécraft made the first filmed infomercial – a 30-minute filmed commercial for the Natural Foods Institute promoting the Vitamix blender. The studio was an early producer of TV spots and made for TV programs.

The copy points used in the 1978 and later Ginsu commercials were used by Ron Popeil, the early TV marketer, in the 1950s. and the Cinécraft Quikut knife commercials produced in the 1960s. ...“Great Scott…a knife that cuts trees!” “And that’s not all.” “Well, What do you know? The other side of the knife is sharp enough for a professional meat cutter.” “The knife’s safeguard handle, beautifully finished in simulated ivory, is boil proof, dishwasher steam proof, and shatterproof.” “guaranteed for life by Quikut.” “The new forked tip, let’s you carve and serve with one hand.” “Yes, but how much? 69 cents! Where?”

Because the brand name "Quikut" was said to lack panache, Ed Valenti, Barry Becher, and copywriter Arthur Schiff created a new brand name that alluded to the exceptional sharpness and durability of a Japanese sword. Ginsu commercials they created promoted “an amazing, low, low price!,” urging viewers to “Order now!” because “Operators are standing by,” and sweetened the pitch with the Ginsu trademark, “But wait, there’s more!” — was an inescapable staple of television in the 1970s. The brand also became a part of pop culture. Johnny Carson sometimes used the knives in his routines, and Jerry Seinfeld did a Ginsu bit on the “Tonight Show.”

Media scholar Robert Thompson, of Syracuse University, called the Ginsu advertising campaign "the pitch of all pitches." "Ginsu has everything a great direct-response commercial could have," said John Witek, a marketing consultant and author of Response Television: Combat Advertising of the 1980s. "Ginsu had humor, demonstration, and a precisely structured series of premium offers I call 'the lots-for-a-little approach'."