# The Metric System Understanding the metric system is pretty easy if you know what the various prefixes mean for example we have kilo which means a thousand hecta which means 100, deca if you think of a decade has ten years deca means ten then you have deci which is one-tenth you have centi if you think of there are a hundred cents in a dollar or hundred years in a century, means 1/100 and milli mean one-thousandth. There are three base units in the metric system there are meters, litres and grams. Meters are used for calculating distances, litres for capacity and gram for weight.

#### What’s up with, metre?

So what exactly is a meter? Well if you were to spread your arms, the distance of your wingspan would be approximately a meter, and the meter’s a little bit larger than a yard, a yard is 36 inches, and a meter is about 39 inches, so it’s slightly larger than a yard. If we were to take those prefixes that we just talked about and attach them to the base unit meter a kilometre would be 1,000 meters if you take hecta and attach it to the word meter it’s a hectometer. You would have 100 meters, and a decameter would be 10 meters a decimeter would be 1/10 of a meter, a very small centimetre it’s like the width of your finger would be 1/100 of a meter. A millimetre is tiny that’s one-thousandth of a meter, you could think of that as maybe the thickness of a dime. #### What is a litre?

When you are at the store, and you’ve seen various beverages on the shelves generally they come in litre bottles and litres are used for capacity. Millilitres which are a thousandth of a litre, you can think of an eyedropper and depending on the size of the eyedropper can hold anywhere from one to maybe ten millilitres. So let’s take the base unit litre and let’s attach our prefixes so a Kilolitre would be a thousand litres, a hectoliter would be 100 litres, a deca leader would be ten litres, a deciliter would be one-tenth of a litre, a centi a litre would be one 100th of a litre, and a millilitre remember that’s a really small amount like an eyedropper that would be one-thousandth of a litre.