Metric prefix

Okay, let's start with numbers. You know that numbers tell us how many things we have. The metric system is a way of measuring how big or small something is, but sometimes the numbers can get really big or really small. That's where metric prefixes come in.

A prefix is a little word that we put in front of a bigger word to change its meaning. For example, the word "unhappy" has the prefix "un-" which means the opposite of happy.

In the metric system, we use prefixes to change the size of the number we're measuring. The most common prefixes are:

- Kilo- (meaning 1000 times bigger)
- Hecto- (meaning 100 times bigger)
- Deca- (meaning 10 times bigger)
- Deci- (meaning 10 times smaller)
- Centi- (meaning 100 times smaller)
- Milli- (meaning 1000 times smaller)

Let's pretend we have some apples. If we have 1000 apples, we could say we have "1 kiloapple." If we have 100 apples, we could say we have "1 hectoapple." If we have 10 apples, we could say we have "1 decaapple." If we have 0.1 apple, we could say we have "1 deciapple." If we have 0.01 apple, we could say we have "1 centiapple." And if we have 0.001 apple, we could say we have "1 milliapple."

It's kind of like when we count by tens, hundreds, and thousands. We can use these prefixes to make it easier to talk about really big or really small things without having to use a lot of zeros.

So, that's basically what metric prefixes are – little words we put in front of other words to change their size. They let us measure things that are really big or really small without making our heads hurt!