What is Rubberducking? An Explanation of the Rubber Duck Debugging Technique

What is Rubberducking? Example explanation: a developer talks through their problem with the “therapist” rubber duck on their desk, only to discover the insight they need. Often useful for debugging.

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Rubberducking is a problem-solving technique where you explain your code or task to a rubber duck—or any inanimate object—and discover the solution yourself through the act of explaining. It's brilliant because it works and is effectively free.

Rubberducking, or rubber ducking, is most commonly associated with debugging in software development but can be applied to any problem-solving process.

The name comes from the book The Pragmatic Programmer by Andrew Hunt and David Thomas. In it, the authors suggest using a rubber duck as a conversation partner to clarify one’s thoughts. This is an accessible and effective way to troubleshoot problems without requiring someone else’s time.

How Rubberducking Works

Have you ever been called over to someone’s desk to help them solve a problem, and as they explain the problem to you or demonstrate it, they figure out the answer themselves? It happens all the time to me, particularly when someone's showing me how something doesn't work, and it magically works just by having me watch over their shoulder.

The rubber duck technique is as simple as that, except that instead of calling someone over, you can simply replace the person with a rubber duck, teddy bear or heck, even your stapler.

The psychology behind rubberducking relies on how explaining a problem forces you to process your thoughts more clearly, often revealing gaps or errors in your understanding. Here’s how you can try it yourself:

1. Set up your “duck”: Place a rubber duck, teddy bear, or any object on your desk.

2. Explain your problem: Describe your code, logic, or issue to the duck, step by step, as if you’re teaching it.

3. Watch for insights: In explaining it aloud, you’ll often uncover what’s wrong or identify a new approach to solving it.

For example, a developer struggling with a bug might explain every line of code to the duck. Verbalising their logic can highlight an overlooked detail that resolves the problem.

Why Rubberducking is Effective

Rubberducking works because it forces you to articulate your thoughts clearly, moving them from abstract notions in your head to concrete statements. This shift can:

• Help you identify assumptions you didn’t realise you were making.

• Reveal errors or gaps in your logic.

• Mimic the process of pair programming without needing another person.

Rubberducking a problem also reduces dependency on others for problem-solving, making it a cost-effective—basically free!—and time-efficient tool for debugging.

Common Scenarios for Rubberducking

Here are some situations where it’s particularly useful:

• Debugging code: Talk through an error or bug in your program.

• Explaining logic: Test the clarity of your solution by explaining it step by step.

• Learning new concepts: Summarise a concept to the duck to check your understanding (see the Feynman Learning Technique)

• Decision-making: Walk through the pros and cons of a decision.

Rubberducking in Software Development

In software development, rubber duck debugging has become a recognised term for this process. It’s so common that some developers keep an actual rubber duck on their desks to symbolise this practice. Teams might 'joke' about needing “a duck” for the simplest bugs.

Debugging is an integral part of coding, and the rubber duck technique makes it less daunting. By verbalising your thought process, you streamline problem-solving without needing external help.

Frequently Asked Questions about Rubberducking

Q: Does it have to be a rubber duck?

Nope. While a rubber duck is the classic choice, you can use anything nearby—your coffee cup, a stapler, or even a photo on your desk.

Q: What if talking out loud isn’t possible?

Writing out your explanation or saying it in your head can work just as well. The key is clarifying and articulating your thought process.

Q: How is this different from pair programming?

Pair programming involves working alongside another person on the same task. Some people swear by pair programming, and to be honest, I've always found it effective whenever I try it. However, rubberducking is a solo activity where the act of explanation itself is the solution.

Next time you're stuck on something, grab a rubber duck and give it a try.

Related Ideas to Rubberducking

Also see:

Rubberducking is similar to the empty chair technique for psychotherapy, which involves speaking to an empty chair as if addressing a person.

It's also easily confused with "rubbernecking," which is slowing down to look at an accident as you drive past—a common cause of traffic jams.

Published 17 Dec 2017

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An eponym is a word named after somebody or someplace. An eponym, almost by definition, comes with a story, making them some of the most intriguing words. Knowing what an eponym is also allows you to use the word eponymous, which is always a good way to sound smart. Some of my favourite eponyms are now commonplace products that took the inventor's name. Some examples: The Rubik's Cube The Rubik's cube is an invention by Hungarian architecture professor Ernő Rubik. The cube has the fascinating property of being a solid object that's also fluid. This year (2024), the Rubik's Cube turned 50, celebrating around half a billion cube sales, scores of speed-cubing championships, and documentaries. When Rubik first invented the cube, he wasn't sure it was solvable and only managed it for the first time several months after creating it. In 2020, Rubik told the story of the cube in his book, Cubed: The Puzzle of Us All. The Jacuzzi The fabulously named jacuzzi, or more generally the hot tub, is named after the Italian Jacuzzi family. The seven brothers of the family—there were also six daughters—trained to become engineers, making plane propellers, irrigation systems and pumps before one of the brothers created a homemade bath to help his two-year-old son who was suffering from rheumatoid arthritis. The rest, as they say, is history. Saskia Solomon tells some of the brothers' story, which includes the court case Jacuzzi vs Jacuzzi, and the invention of the jacuzzi in the 2023 New York Times article, The Frothy Saga of the Jacuzzi Family. The Sandwich After so long as what seems the most basic of foods, it was remarkable for me to learn that the humble sandwich was named after a person: John Montague, the 4th Earl of Sandwich. Though he probably spent most of his time in London, the title itself is associated with the small town of Sandwich in Kent, in Southeast England. The story goes that the Earl liked playing cards and wanted food he could eat without having to leave his game and that wouldn't give him sticky fingers that would damage the cards. Incarnations of open sandwiches appeared much earlier elsewhere. For example, the trencher—something I had to look up when reading Game of Thrones—involved serving food on top of old bread as a sort of plate. But it took the Earl's dedication to card playing, or at least desk work, to take the next step many years later. The Biro and BiC ballpoint pens László Bíró was a Hungarian-Argentine inventor who created the first truly successful ballpoint pen. In the US, the BiC is more common, an eponym this time from Marcel Bich. It's said that Lázló experienced his fountain pen leaking from heat—fountain pens being very common before the ballpoint—and was inspired by a printing press that used a cylinder to spread the ink. All it needed was to go in all directions. Enter the ballpoint. While the invention seems obvious in hindsight, perfecting it for robust, commercial use was challenging. For example, finding suitable ink for the tiny ball bearing to spread, which doesn't leak or clog and isn't overly affected by heat. Lázló teamed up with an aviation company—who use a lot of ball bearings—which also provided a great use case of finding a pen that wouldn't leak from the air pressure changes in planes. Later, BiC licenced the technology from Biro. A Bic Cristal® Ballpoint pen is part of the collection at the MoMA. Silhouette I only learned that silhouette was an eponym while preparing this sketch, but it's perhaps the best of all. Étienne de Silhouette, a French government finance official tasked with curbing a French deficit in the 1700s, unwittingly gave his name to the classic black-on-white simple outline image of a person. His severe frugal policies of taxes, curbing royal spending and even melting down gold and silverware earned him the reputation of doing things cheaply. Hence, a cheap method of creating a portrait, cutting out black paper and laying it on a white background, became known as a silhouette. Diesel Nearly everyone will recognise the fuel that Rudolf Diesel gave his name to and his diesel engine. Diesel created a breakthrough engine that was more efficient than typical steam engines while being smaller and weighing less. Curiously, I learned that Diesel died in mysterious circumstances, disappearing on a journey across the English Channel in 1913. -- An excellent episode of the 99% Invisible podcast featuring Helen Zaltzman of the Allusionist raised several interesting questions about eponyms I hadn't considered. Here are a few to think about: Eponyms are common in medicine, for example, when we name a disease or condition after those playing a part in the discovery. However, the name, for example, Creutzfeldt-Jakob disease, tells a medical practitioner very little about the disease compared to a name that relates to the symptoms of the sufferer or the cause. Should examples like these be replaced with more practical names? Eponyms almost always have a way of oversimplifying a story, often wrapping up complex histories with the names of white males. For example, rarely are products invented or diseases identified solely through the actions of one person. Yet an eponym chooses one, or some people, at the expense of others. Eponyms may be the name of someone later discredited or who develops a tarnished reputation from other actions in their lives. Should someone who did evil deeds be remembered in an eponym or should it be changed? Who knew eponyms could be so interesting? Know some good eponyms with fun stories? I'd love to hear them. Eponyms are distinct from the fun concept of Nominative determinism—an aptronym—where someone's name seemingly influenced their future actions or career choices (for example, Les McBurney — Volunteer firefighter). I've covered a lot of eponyms over the years, far more than I realised. Using the handy list page on the site, I've collected some other eponym examples, which include a lot of my favourites: Bloom's Taxonomy Bortle Scale Braille Campbell's law Chesterton's fence Conway's Law Dracula sneeze Dunbar's number: 150 Fahrenheit and Celsius Fitts' Law Goldilocks tasks Goodhart's Law Hanlon's Razor Hofstadter's Law Identify a Douglas fir Jevon's Paradox Johari window Koomey's Law The Kano model Marchetti's constant Maslow's hierarchy of needs Metcalfe's Law Möbius strip Moore's Law Muphry's Law Pyrrhic victory Russell's Teapot Sankey diagram Scoville scale Spoonerisms Strahler stream order The Abilene paradox The Barnum effect The Betty Crocker Effect The Boaty McBoatface effect The Diderot Effect The Doppler Effect The Droste effect The Feynman Learning Technique The Gartner Hype cycle The Generalised Peter Principle The Gini coefficient The Goldilocks Zone The IKEA effect The Keeling curve The Lake Wobegon Effect The Lucretius problem The Mercator projection The Monty Hall problem The Overton Window The Oxford comma The Peter Principle The Plimsoll line The Pomodoro Technique ® The Rashomon effect The Rosetta Stone The Shirky Principle The Streisand Effect The Stroop test Veblen goods Other fun -onym words about words: Acronyms and initialisms Capitonym Heteronym Homonyms, homographs, homophones… …An eponym is a word named after somebody or someplace. An eponym, almost by definition, comes with a story, making them some of the most intriguing words. Knowing what an eponym is also allows you to use the word eponymous, which is always a good way to sound smart. Some of my favourite eponyms are now commonplace products that took the inventor's name. Some examples: The Rubik's Cube The Rubik's cube is an invention by Hungarian architecture professor Ernő Rubik. The cube has the fascinating property of being a solid object that's also fluid. This year (2024), the Rubik's Cube turned 50, celebrating around half a billion cube sales, scores of speed-cubing championships, and documentaries. When Rubik first invented the cube, he wasn't sure it was solvable and only managed it for the first time several months after creating it. In 2020, Rubik told the story of the cube in his book, Cubed: The Puzzle of Us All. The Jacuzzi The fabulously named jacuzzi, or more generally the hot tub, is named after the Italian Jacuzzi family. The seven brothers of the family—there were also six daughters—trained to become engineers, making plane propellers, irrigation systems and pumps before one of the brothers created a homemade bath to help his two-year-old son who was suffering from rheumatoid arthritis. The rest, as they say, is history. Saskia Solomon tells some of the brothers' story, which includes the court case Jacuzzi vs Jacuzzi, and the invention of the jacuzzi in the 2023 New York Times article, The Frothy Saga of the Jacuzzi Family. The Sandwich After so long as what seems the most basic of foods, it was remarkable for me to learn that the humble sandwich was named after a person: John Montague, the 4th Earl of Sandwich. Though he probably spent most of his time in London, the title itself is associated with the small town of Sandwich in Kent, in Southeast England. The story goes that the Earl liked playing cards and wanted food he could eat without having to leave his game and that wouldn't give him sticky fingers that would damage the cards. Incarnations of open sandwiches appeared much earlier elsewhere. For example, the trencher—something I had to look up when reading Game of Thrones—involved serving food on top of old bread as a sort of plate. But it took the Earl's dedication to card playing, or at least desk work, to take the next step many years later. The Biro and BiC ballpoint pens László Bíró was a Hungarian-Argentine inventor who created the first truly successful ballpoint pen. In the US, the BiC is more common, an eponym this time from Marcel Bich. It's said that Lázló experienced his fountain pen leaking from heat—fountain pens being very common before the ballpoint—and was inspired by a printing press that used a cylinder to spread the ink. All it needed was to go in all directions. Enter the ballpoint. While the invention seems obvious in hindsight, perfecting it for robust, commercial use was challenging. For example, finding suitable ink for the tiny ball bearing to spread, which doesn't leak or clog and isn't overly affected by heat. Lázló teamed up with an aviation company—who use a lot of ball bearings—which also provided a great use case of finding a pen that wouldn't leak from the air pressure changes in planes. Later, BiC licenced the technology from Biro. A Bic Cristal® Ballpoint pen is part of the collection at the MoMA. Silhouette I only learned that silhouette was an eponym while preparing this sketch, but it's perhaps the best of all. Étienne de Silhouette, a French government finance official tasked with curbing a French deficit in the 1700s, unwittingly gave his name to the classic black-on-white simple outline image of a person. His severe frugal policies of taxes, curbing royal spending and even melting down gold and silverware earned him the reputation of doing things cheaply. Hence, a cheap method of creating a portrait, cutting out black paper and laying it on a white background, became known as a silhouette. Diesel Nearly everyone will recognise the fuel that Rudolf Diesel gave his name to and his diesel engine. Diesel created a breakthrough engine that was more efficient than typical steam engines while being smaller and weighing less. Curiously, I learned that Diesel died in mysterious circumstances, disappearing on a journey across the English Channel in 1913. -- An excellent episode of the 99% Invisible podcast featuring Helen Zaltzman of the Allusionist raised several interesting questions about eponyms I hadn't considered. Here are a few to think about: Eponyms are common in medicine, for example, when we name a disease or condition after those playing a part in the discovery. However, the name, for example, Creutzfeldt-Jakob disease, tells a medical practitioner very little about the disease compared to a name that relates to the symptoms of the sufferer or the cause. Should examples like these be replaced with more practical names? Eponyms almost always have a way of oversimplifying a story, often wrapping up complex histories with the names of white males. For example, rarely are products invented or diseases identified solely through the actions of one person. Yet an eponym chooses one, or some people, at the expense of others. Eponyms may be the name of someone later discredited or who develops a tarnished reputation from other actions in their lives. Should someone who did evil deeds be remembered in an eponym or should it be changed? Who knew eponyms could be so interesting? Know some good eponyms with fun stories? I'd love to hear them. Eponyms are distinct from the fun concept of Nominative determinism—an aptronym—where someone's name seemingly influenced their future actions or career choices (for example, Les McBurney — Volunteer firefighter). I've covered a lot of eponyms over the years, far more than I realised. Using the handy list page on the site, I've collected some other eponym examples, which include a lot of my favourites: Bloom's Taxonomy Bortle Scale Braille Campbell's law Chesterton's fence Conway's Law Dracula sneeze Dunbar's number: 150 Fahrenheit and Celsius Fitts' Law Goldilocks tasks Goodhart's Law Hanlon's Razor Hofstadter's Law Identify a Douglas fir Jevon's Paradox Johari window Koomey's Law The Kano model Marchetti's constant Maslow's hierarchy of needs Metcalfe's Law Möbius strip Moore's Law Muphry's Law Pyrrhic victory Russell's Teapot Sankey diagram Scoville scale Spoonerisms Strahler stream order The Abilene paradox The Barnum effect The Betty Crocker Effect The Boaty McBoatface effect The Diderot Effect The Doppler Effect The Droste effect The Feynman Learning Technique The Gartner Hype cycle The Generalised Peter Principle The Gini coefficient The Goldilocks Zone The IKEA effect The Keeling curve The Lake Wobegon Effect The Lucretius problem The Mercator projection The Monty Hall problem The Overton Window The Oxford comma The Peter Principle The Plimsoll line The Pomodoro Technique ® The Rashomon effect The Rosetta Stone The Shirky Principle The Streisand Effect The Stroop test Veblen goods Other fun -onym words about words: Acronyms and initialisms Capitonym Heteronym Homonyms, homographs, homophones…

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