Kilometre

A kilometre is a way to measure length.

It is made of one thousand metres. People use it to measure distances on land. Most of the world uses this unit.

Some places use different ways to measure. The United States and United Kingdom use miles. This is a different way to tell length.

In the past, people used other names. Some used a name called myriametre. Now, the kilometre is the main unit.

Some people call it a klick. This is a slang word used by soldiers. It is a fun way to say it.

A kilometre is a way to measure length.

It is part of the SI system. This is a global way to measure things. One kilometre is equal to one thousand metres. The symbol for it is km. Most people use it to measure land distances. The United States and United Kingdom use miles instead.

People say the word in two ways. Some put the stress on the first part. This follows the way we say kilogram. Others put the stress on the second part. This sounds like the word thermometer. In Australia, the government picked the first way. But the prime minister liked the second way. He liked it because of its Greek roots.

Long ago, France made a new system. They used the metre to measure distance. At first, people used a unit called the myriametre. This was ten thousand metres long. In 1935, the myriametre was stopped. The kilometre became the main unit for that size. In the US and UK, soldiers sometimes say "klick." This is a slang word for a kilometre.

A kilometre is a way to measure length.

It is part of the International System of Units, or SI. One kilometre is equal to one thousand metres. The prefix "kilo-" means one thousand. Most people use it to measure distances on land. This includes distances between different places. The United States and the United Kingdom are exceptions. They use the statute mile instead. The symbol for a kilometre is km.

There are two common ways to say the word. Some people put the stress on the first part. This sounds like the word kilogram. The BBC and ABC use this way. Other people stress the second part of the word. This sounds like the word thermometer. This way is used in many countries. It is different from how other SI units work. This happens because the stress pattern is irregular.

Long ago, France wanted a new way to measure. The French National Constituent Assembly ordered this in 1790. In 1793, they made the metre the main unit. They based it on the distance from the poles to the Equator. The first name for a kilometre was "Millaire." Later, people often used the myriametre instead. One myriametre is ten thousand metres.

Different places used different names for a long time. The Dutch used the kilometre in 1817. They called it a "mijl." In the Netherlands, it became the official unit in 1867. By 1842, the kilometre was used in Italy. In 1935, the myriametre was officially stopped. The International Committee for Weights and Measures abolished the prefix "myria-" then. This left the kilometre as the main unit.

We can compare a kilometre to many other things. One kilometre is about 0.621 miles. It is also about 540 nautical miles. You can even compare it to space measurements. It is much smaller than an astronomical unit. It is also smaller than a light-year or a parsec. In the US and UK militaries, soldiers use a slang term. They call a kilometre a "klick."

The kilometre is a fundamental unit of length. It belongs to the International System of Units, known as the SI. In American English, it is spelled kilometer. This unit is essential for measuring distances on land. Most countries in the world use it to express how far apart geographical places are. However, the United States and the United Kingdom are notable exceptions. These nations prefer to use the statute mile instead.

To understand the kilometre, you must understand its name. The word uses the SI prefix "kilo-". In this system, "kilo-" means one thousand. Therefore, one kilometre is exactly equal to one thousand metres. The official symbol for this unit is "km". This symbol is always written in lower case. The International Bureau of Weights and Measures, or BIPM, has standardised this symbol.

There is a debate regarding how to pronounce the word. One common way follows a specific pattern used for other SI units. In this version, the stress is placed on the first syllable. This matches words like kilogram, kilojoule, or kilohertz. This pronunciation is preferred by organizations like the BBC, CBC, and ABC. The second way places the stress on the second syllable. This pattern is similar to measuring instruments like a thermometer or a barometer. This second way is considered irregular for an SI unit. In Australia, a dispute even occurred over this. The government's Metric Conversion Board declared the first way official in 1970. However, Prime Minister Gough Whitlam insisted the second way was correct due to Greek origins.

The history of this measurement began in France. On 8 May 1790, the French National Constituent Assembly issued a decree. They ordered the French Academy of Sciences to create a new system. By August 1793, the French National Convention made the metre the sole length measurement. This metre was based on a specific scientific calculation. It was one millionth of the distance from the orbital poles to the Equator. This was intended to be a truly international unit.

Early names for the kilometre were quite different. Its first name was "Millaire." For many years, people preferred a different unit called the myriametre. A myriametre is equal to ten thousand metres. This term appeared in the 1802 book Physique d'Emile. In 1835, French maps used both myriametres and "lieues de Poste." These postal leagues were about 4 kilometres long. Eventually, the myriametre was removed from use. In 1935, the International Committee for Weights and Measures officially abolished the prefix "myria-". This left the kilometre as the recognised unit for that scale.

Different European nations adopted the unit at different times. The Dutch began using the kilometre in 1817. They initially gave it the local name "mijl." It was not until 1867 that it became the only official unit in the Netherlands. Textbooks from 1842 and 1848 show how the unit spread. By that time, the kilometre was used in Italy and the Netherlands. Meanwhile, France was still using the myriametre. This shows how slowly measurement standards can change across borders.

We can compare the kilometre to many other units of length. One kilometre is approximately 0.621 miles. It is also about 0.540 nautical miles. When looking at much larger scales, the kilometre is quite small. It is much smaller than an astronomical unit. It is also much smaller than a light-year or a parsec. In certain circles, the word even has a slang version. Soldiers in the US, UK, and Canadian militaries often call a kilometre a "klick."