What is a robot? Explained from the ground up

Most people have seen a robot. Perhaps a robot vacuum cleaner moving around the floor. Perhaps a robot lawnmower at a neighbour's. Perhaps a robot arm in a film about a car factory.

And yet the question of what a robot is is hard to answer. Is the vacuum cleaner a robot? Is a remote-controlled toy car a robot? Is the washing machine a robot?

The answer has been written down. There is even an international standard for it, and it is surprisingly easy to read once it has been translated. We start there.

The word is a hundred years old and comes from a play

The word robot comes from a play, not from the technology.

In 1920 the Czech writer Karel Čapek published the play R.U.R., "Rossum's Universal Robots".³¹ It opened on 2 January 1921.³¹ In the play, artificial workers are made in a factory, and they are called robots. As far as is known, it is the first time the word is used in anything like today's meaning.³⁰

Čapek himself said he did not invent the word.³⁰ He explained in a letter, and later in a newspaper article, that it was his brother Josef who suggested it.³⁰ Karel had planned to call the figures "laboři", after the Latin word for work.³⁰ He did not like the word and asked his brother.

The word robota means work in Slavic languages.² More exactly, it means heavy, monotonous and forced labour.² In the past it referred to the days of the week when peasants had to leave their own farm and work unpaid on the landowner's land.

One detail in the play is worth noting. The robots in it were not robots by today's definition. They were not machines. They were artificial living beings of some kind of flesh and blood.³⁰ Today we would call them androids. So the word robot meant something different on the day it was invented from what it means now.

The play was a hit, and the word spread. It pushed out older words such as "automaton" and "android" in languages all over the world.

What counts as a robot: the formal definition, in plain words

There is an international standard that sets out what the words in robotics mean. It is called ISO 8373. A standard is a document that experts from many countries have agreed on, so that everyone means the same thing when they say the same word. The first version came in 1994 and the one in force now came in 2021.^{20, 21}

Four words that decide

The standard says that a robot is a programmed, actuated mechanism with a degree of autonomy, which performs locomotion, manipulation or positioning.^{5, 20}

It sounds dry. We will take it word by word.

Programmed means that someone has told it what to do.

Actuated means that it has motors or something else that makes it move under its own power.

Autonomy is the word that makes all the difference. The standard defines autonomy as the ability to perform its task based on the current state and what it senses, without a human stepping in.²⁰ So the robot reads something and decides its next movement itself.

Locomotion, manipulation or positioning means that it moves itself, moves things, or puts something in the right place.

The answers to the questions at the start

Now we can answer the questions from the start.

The robot vacuum cleaner is a robot. It senses where the walls are and decides for itself how to drive.

The remote-controlled toy car is not a robot. It only does what you tell it at the moment you tell it. The car is controlled directly by the user.

The washing machine is not a robot either. It runs a programme you chose. It does not sense your clothes and change its mind.

The standard even has its own term for machines like these that are almost robots: robotic device. These are mechanisms built with robotic technology that do not meet all the properties of a robot. In the older 2012 edition the criterion was stated outright: the mechanism lacked either enough axes of movement or the degree of autonomy.²¹ A remote-controlled machine ends up there.

The same machine can be two different things

Here is something that confuses most people, and it is worth understanding properly.

The standard divides robots into industrial robots, service robots and medical robots. But the division is made by what the robot is used for, not by how it is built.²⁰

An industrial robot is defined as an automatically controlled, reprogrammable, multipurpose manipulator, programmable in three or more axes.^{5, 20} "Manipulator" is the technical term for the part that does the actual work, usually an arm.

The point is that a robot arm welding in a car factory is an industrial robot. An almost identical robot arm putting food on a plate in a restaurant is a service robot.^{20, 21} Same machine, different answer, because the use is different.

So it is the job that decides what a robot is, not the shape.

The first real industrial robot started work in 1961

The first industrial robot actually put into service on a production line started work in 1961, at a car maker in New Jersey in the United States.^{6, 7} It was called Unimate.

The inventor George Devol filed the patent application on 10 December 1954.²⁷ The patent was not granted until 13 June 1961, and it was called "Programmed Article Transfer".²⁷

The robot weighed about 1,360 kilograms and could lift up to 45 kilograms.^{6, 7} Its job was to take newly cast metal parts out of a die-casting machine.^{6, 7} The parts were red-hot metal.

There is a detail in the story that is easy to miss. The workers did not protest. Standing and picking red-hot metal out of a machine is described in the sources as a job nobody wanted.^{6, 7} The protests came later, almost ten years afterwards, when a much larger robot installation was put in place at another factory.⁶

That says something about the whole subject. The question of robots is rarely just yes or no. It is about which job, at what pace and in whose factory.

Where robots are sold, and in what volumes

Now to the figures. They refer to 2024 unless otherwise stated, and they come from the International Federation of Robotics, the organisation that collects the world's robot statistics together with the industry associations in different countries.^{9, 24}

In 2024, 542,076 new industrial robots were installed in the world.²⁴ That is the second highest number ever. The record is 552,946 from 2022.²⁴

In total there were about 4.66 million industrial robots in operation in the world in 2024, a rise of 9% in one year.^{9, 24}

74% of all new industrial robots in 2024 were installed in Asia. Europe got 16% and the Americas as a whole 9%.^{9, 24}

The car industry was not the largest in 2024. The electronics industry was the largest with 24% of installations, the car industry came second with 23%, and metal and machinery third with 16%.²⁴ The picture of the robot as a car factory machine was true for a long time, but it is no longer true globally.²⁴

And now the figure that changes the whole perspective. Alongside the industrial robots, nearly 20.1 million service robots for consumer use were sold in 2024.^{11, 12} Robots for household tasks, in practice floor cleaning and lawn mowing, made up 97% of them.^{11, 12} Just over 199,000 professional service robots and just under 16,700 medical robots were sold.^{11, 12}

Do the sums. In one year about 20 million robots were sold to ordinary homes and just over half a million industrial robots to factories. A single year's sales to homes is several times larger than the world's entire stock of industrial robots in operation.^{12, 24} The figures for home robots come from the 294 suppliers that reported to the IFR and are therefore a minimum.¹¹ The organisation also advises against setting figures from different World Robotics reports against each other, so the comparison above shows orders of magnitude and not exact proportions. The robots sold in the largest numbers do not look the way we have learned robots look.

Sweden is one of the most robot-automated countries in the world

The measure used to compare countries is called robot density. It is the number of industrial robots in operation divided by the number of employees in manufacturing, counted per 10,000 employees.¹⁰

Sweden's place in the table

Sweden had 377 robots per 10,000 employees in 2024, which is fifth place in the world.¹⁰

Ahead of Sweden are South Korea with 1,220, Singapore with 818, Germany with 449 and Japan with 446.¹⁰ After Sweden come Denmark with 329, Slovenia with 315, the United States with 307, Taiwan with 302 and Switzerland with 294.¹⁰ China, where more than half of the world's new industrial robots were installed in 2024, is still in 22nd place in the table, after the country's statistics bureau revised its labour market figures.¹⁰

The world average was 132 robots per 10,000 employees and the average for the EU's 27 countries was 231.^{10, 24} The figure 132 comes from the statistics producer's latest table, published in April 2026.¹⁰ The same producer's report from September 2025 instead gives 177 for the same year, before China's employment data was revised, and 162 for the year before.^{24, 25} Sweden is well above both the world average and the EU average.

Why the ratio should be read with care

But read the measure with care, because it is a ratio. Robot density is robots divided by employees. So the figure can go up if industry shrinks, and down if industry grows and hires, without a single robot being moved. You can see it in China's placing. The statistics producer states that the country ends up in 22nd place after the Chinese statistics bureau provided updated labour market data, that is, after a change in the denominator and not in the number of robots.¹⁰

Sweden saw this in practice. For the statistics year 2023 the Swedish robotics association reported 1,849 new robot installations, a rise of 13% on the year before, and a stock of 17,436 robots in Swedish industry.^{13, 14} The same year China moved into third place in the robot density table and pushed down the countries below it, Sweden included.²⁶ More robots, a lower placing. Both facts were true.

Why a robot can weld a car but not fold a towel

Now the most interesting question in the whole subject.

A robot can weld a car with a precision of a tenth of a millimetre, around the clock, for years. The same robot cannot fold a towel. It cannot pick a dishcloth out of a full dish rack. It cannot find the keys in a messy hallway.

This pattern has a name. In 1988 the researcher Hans Moravec wrote that it is comparatively easy to make computers perform at adult level on intelligence tests or at games, and difficult or impossible to give them the skills of a one-year-old in perception and movement.^{29, 32} Several researchers put forward similar ideas in the 1980s, among them Rodney Brooks and Marvin Minsky.¹⁵

Moravec's own explanation is that sight and movement have developed over an immensely long time in animals and humans, and are therefore deeply practised and feel easy to us, while abstract thinking is a recent ability that we are not actually very good at.^{29, 32}

The observation is not undisputed, and that should be said. Allen Newell called the idea a myth as early as 1983.²⁸ The researcher Arvind Narayanan has described it as a statement about what AI research thinks is worth working on, rather than a prediction of what will turn out easy or hard.²⁹

But it still explains something important. That a robot is impressive in a factory says almost nothing about how it copes in a kitchen.

A factory is built to be predictable. The parts arrive in the same place every time, the light is the same, the floor is flat. A home is the opposite. That is why robots came to factories first, and it is why the robots sold to homes do one simple thing: vacuum the floor or cut the grass.

Humanoid robots: what is promise and what is outcome

Robots that look like people get a lot of attention right now, and very large volumes are being talked about for the years ahead.

This is the current situation according to a review in the technical trade press from September 2025: most of the market is still hypothetical.¹⁶ The most successful companies have deployed a small number of robots in carefully controlled trials.¹⁶ The obstacles pointed out are demand, battery life, reliability and safety.¹⁶

A few figures from the same review make the problem concrete. Industrial customers often expect 99.99% reliability, because a stop on a production line can cost tens of thousands of dollars a minute.¹⁶ At 99%, according to the review's own worked example, that means about five hours of downtime a month.¹⁶ The difference between 99 and 99.99 is the difference between a demonstration and a job.

The same review also points out something simpler. In the short and medium term, robots with arms and wheels instead of legs are more reliable, more energy efficient and cheaper for exactly the settings shown in the demonstration videos.¹⁶

One market analysis gives about 16,000 humanoid robots installed in the world in 2025, more than 80% of them in China.¹⁷ Set the 16,000 for 2025 against 542,076 industrial robots for 2024, and the proportions become clear.^{17, 24}

This is familiar from the history of AI, which we went through in the AI timeline: the field has promised more than it could deliver before. That does not mean the promise is false this time. It means that the difference between pilot and operation is the only difference worth measuring.

One last thing: the word cobot does not mean what most people think

You will come across the word cobot, or collaborative robot. It is usually described as a robot you can work next to without a safety cage.

The safety rules for industrial robots are in the standard ISO 10218, in two parts.^{22, 23} A new edition of part 1 came in February 2025 and replaced the one from 2011.²² The requirements for robots that work close to people were in a separate document, ISO/TS 15066 from 2016. Most of them are now included in ISO 10218, above all in part 2 on applications and robot cells.^{22, 23}

And the new edition does something interesting with language. It avoids the terms "collaborative robot" and "collaborative operation."^{22, 23} Instead it talks about a collaborative application: it is the robot, the task, the tool and the environment together that can be assessed as safe to work with, not the robot on its own.²²

So you cannot buy a safe robot, only build an installation that has been assessed as safe. If you change the gripper or the task, the assessment must be done again, whatever the robot's product sheet says.²²

What to take away

A robot is an actuated machine that senses something and decides its next movement itself. In 2024, 542,076 industrial robots were installed in the world and the stock was about 4.66 million, while nearly 20.1 million service robots for consumer use were sold.^{11, 12, 24} Sweden had 377 robots per 10,000 employees, fifth place in the world.¹⁰ The structural point is where the volume lies and how the measure behaves. Homes take in robots on a different scale from factories, and robot density is a ratio that can move when the denominator changes, as China's 22nd place after revised employment data shows.^{10, 12, 24} Follow the International Federation of Robotics' World Robotics for industry and service, and the number of installed humanoid robots, 16,000 in 2025 according to a market analysis.^{11, 17, 24}

The next episode is S1:E3 Cybersecurity, about what counts as an incident and how incidents are counted in Sweden.

Education, not advice.