KISS principle
Encyclopedia
KISS is an acronym for the design principle Keep it simple, Stupid!. Other variations include "keep it simple and stupid", "keep it short and simple", "keep it simple sir", "keep it simple or be stupid" or "keep it simple and straightforward". The KISS principle states that most systems work best if they are kept simple rather than made complex, therefore simplicity
should be a key goal in design
and unnecessary complexity should be avoided.
, lead engineer at the Lockheed
Skunk Works
(creators of the Lockheed U-2
and SR-71 Blackbird
spy planes, among many others).
While popular usage translates it as 'Keep it simple, stupid', Johnson translated it as 'Keep it simple stupid', and this reading is still used by many authors. There was no implicit meaning that an engineer was stupid; just the opposite.
The principle is best exemplified by the story of Johnson handing a team of design engineers a handful of tools, with the challenge that the jet aircraft they were designing must be repairable by an average mechanic in the field under combat conditions with only these tools. Hence, the 'stupid' refers to the relationship between the way things break and the sophistication available to fix them.
The acronym is used by many in the United States Air Force
and field of software development
.
, and Albert Einstein
's maxim that "everything should be made as simple as possible, but no simpler". Leonardo da Vinci
's "Simplicity is the ultimate sophistication", or Antoine de Saint Exupéry's "It seems that perfection is reached not when there is nothing left to add, but when there is nothing left to take away". Colin Chapman
, the founder of Lotus Cars
, urged his designers to "Simplify, and add lightness". Rube Goldberg's machines
, intentionally overly-complex solutions to simple tasks or problems, are humorous examples of "non-KISS" solutions.
Instruction creep
and function creep, two instances of creeping featuritis, are examples of failure to follow the KISS principle in software development
. Similarly, scope creep
exemplifies failure to follow KISS in project management.
, and Disney's Nine Old Men
write about it in Disney Animation: The Illusion of Life
, which is considered "the animation bible" by CG, traditional and stop motion animators. Inexperienced animators may "overanimate", or make their character move too much and do too much, such as carrying every accent over into body language, facial expression, and lipsync. Williams urges animators to "KISS".
Simplicity
Simplicity is the state or quality of being simple. It usually relates to the burden which a thing puts on someone trying to explain or understand it. Something which is easy to understand or explain is simple, in contrast to something complicated...
should be a key goal in design
Design
Design as a noun informally refers to a plan or convention for the construction of an object or a system while “to design” refers to making this plan...
and unnecessary complexity should be avoided.
Origin
The acronym was first coined by Kelly JohnsonClarence Johnson
Clarence Leonard "Kelly" Johnson was an aircraft engineer and aeronautical innovator. As a member and first team leader of the Lockheed Skunk Works, Johnson worked for more than four decades and is said to have been an "organizing genius"...
, lead engineer at the Lockheed
Lockheed Martin
Lockheed Martin is an American global aerospace, defense, security, and advanced technology company with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta in March 1995. It is headquartered in Bethesda, Maryland, in the Washington Metropolitan Area....
Skunk Works
Skunk works
Skunk Works is an official alias for Lockheed Martin’s Advanced Development Programs , formerly called Lockheed Advanced Development Projects. Skunk Works is responsible for a number of famous aircraft designs, including the U-2, the SR-71 Blackbird, the F-117 Nighthawk, and the F-22 Raptor...
(creators of the Lockheed U-2
Lockheed U-2
The Lockheed U-2, nicknamed "Dragon Lady", is a single-engine, very high-altitude reconnaissance aircraft operated by the United States Air Force and previously flown by the Central Intelligence Agency . It provides day and night, very high-altitude , all-weather intelligence gathering...
and SR-71 Blackbird
SR-71 Blackbird
The Lockheed SR-71 "Blackbird" was an advanced, long-range, Mach 3+ strategic reconnaissance aircraft. It was developed as a black project from the Lockheed A-12 reconnaissance aircraft in the 1960s by the Lockheed Skunk Works. Clarence "Kelly" Johnson was responsible for many of the...
spy planes, among many others).
While popular usage translates it as 'Keep it simple, stupid', Johnson translated it as 'Keep it simple stupid', and this reading is still used by many authors. There was no implicit meaning that an engineer was stupid; just the opposite.
The principle is best exemplified by the story of Johnson handing a team of design engineers a handful of tools, with the challenge that the jet aircraft they were designing must be repairable by an average mechanic in the field under combat conditions with only these tools. Hence, the 'stupid' refers to the relationship between the way things break and the sophistication available to fix them.
The acronym is used by many in the United States Air Force
United States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
and field of software development
Software developer
A software developer is a person concerned with facets of the software development process. Their work includes researching, designing, developing, and testing software. A software developer may take part in design, computer programming, or software project management...
.
Variants
The principle most likely finds its origins in similar concepts, such as Occam's razorOccam's razor
Occam's razor, also known as Ockham's razor, and sometimes expressed in Latin as lex parsimoniae , is a principle that generally recommends from among competing hypotheses selecting the one that makes the fewest new assumptions.-Overview:The principle is often summarized as "simpler explanations...
, and Albert Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...
's maxim that "everything should be made as simple as possible, but no simpler". Leonardo da Vinci
Leonardo da Vinci
Leonardo di ser Piero da Vinci was an Italian Renaissance polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist and writer whose genius, perhaps more than that of any other figure, epitomized the Renaissance...
's "Simplicity is the ultimate sophistication", or Antoine de Saint Exupéry's "It seems that perfection is reached not when there is nothing left to add, but when there is nothing left to take away". Colin Chapman
Colin Chapman
Anthony Colin Bruce Chapman CBE was an influential British designer, inventor, and builder in the automotive industry, and founder of Lotus Cars....
, the founder of Lotus Cars
Lotus Cars
Lotus Cars is a British manufacturer of sports and racing cars based at the former site of RAF Hethel, a World War II airfield in Norfolk. The company designs and builds race and production automobiles of light weight and fine handling characteristics...
, urged his designers to "Simplify, and add lightness". Rube Goldberg's machines
Rube Goldberg machine
A Rube Goldberg machine, contraption, device, or apparatus is a deliberately over-engineered or overdone machine that performs a very simple task in a very complex fashion, usually including a chain reaction...
, intentionally overly-complex solutions to simple tasks or problems, are humorous examples of "non-KISS" solutions.
Instruction creep
Instruction creep
Instruction creep occurs when instructions increase in number and size over time until they are unmanageable. It can be insidious and damaging to the success of large groups such as corporations, originating from ignorance of the KISS principle and resulting in overly complex procedures that are...
and function creep, two instances of creeping featuritis, are examples of failure to follow the KISS principle in software development
Software development
Software development is the development of a software product...
. Similarly, scope creep
Scope creep
Scope Creep in project management refers to uncontrolled changes or continuous growth in a project's scope. This phenomenon can occur when the scope of a project is not properly defined, documented, or controlled...
exemplifies failure to follow KISS in project management.
In film animation
Master animator Richard Williams explains the KISS principle in his book The Animator's Survival KitThe Animator's Survival Kit
The Animator's Survival Kit: A Manual of Methods, Principles, and Formulas for Classical, Computer, Games, Stop Motion, and Internet Animators is a book by award-winning animator and director Richard Williams about various aspects of animation...
, and Disney's Nine Old Men
Disney's Nine Old Men
Disney's Nine Old Men were the core animators at The Walt Disney Company who created some of Disney's most famous works, from Snow White and the Seven Dwarfs onward to The Rescuers. Walt Disney jokingly called this group of animators his "Nine Old Men," referring to Robert S...
write about it in Disney Animation: The Illusion of Life
Disney Animation: The Illusion of Life
Disney Animation: The Illusion of Life , 1981, is an acclaimed book by two of Disney's Nine Old Men, Ollie Johnston and Frank Thomas. It is widely considered to be one of the best books ever published on the topic of character animation...
, which is considered "the animation bible" by CG, traditional and stop motion animators. Inexperienced animators may "overanimate", or make their character move too much and do too much, such as carrying every accent over into body language, facial expression, and lipsync. Williams urges animators to "KISS".
See also
- ChartjunkChartjunkChartjunk refers to all visual elements in charts and graphs that are not necessary to comprehend the information represented on the graph, or that distract the viewer from this information....
- Don't repeat yourselfDon't repeat yourselfIn software engineering, Don't Repeat Yourself is a principle of software development aimed at reducing repetition of information of all kinds, especially useful in multi-tier architectures...
(DRY) - List of software development philosophies
- Minimalism
- Occam's razorOccam's razorOccam's razor, also known as Ockham's razor, and sometimes expressed in Latin as lex parsimoniae , is a principle that generally recommends from among competing hypotheses selecting the one that makes the fewest new assumptions.-Overview:The principle is often summarized as "simpler explanations...
- Pareto principlePareto principleThe Pareto principle states that, for many events, roughly 80% of the effects come from 20% of the causes.Business-management consultant Joseph M...
80:20 rule - Parsimony
- W. Heath RobinsonW. Heath RobinsonWilliam Heath Robinson was an English cartoonist and illustrator, best known for drawings of eccentric machines....
- Rule of Least Power
- The Fox and the Cat (fable)The Fox and the Cat (fable)The Fox and the Cat is an ancient fable, with both Eastern and Western analogues involving different animals, that addresses the difference between resourceful expediency and a master strategem. Included in collections of Aesop's fables since the start of printing in Europe, it is number 605 in the...
- Worse is betterWorse is betterWorse is better, also called the New Jersey style, was conceived by Richard P. Gabriel to describe the dynamics of software acceptance, but it has broader application. The idea is that quality does not necessarily increase with functionality. There is a point where less functionality is a...
(Less is More) - You ain't gonna need itYou Ain't Gonna Need It"You ain't gonna need it" is the principle in extreme programming that programmers should not add functionality until it is necessary...
(YAGNI)