# Metric systems

Back in the old times, people used their body parts to measure a particular object, or tell the distance of one place and another. Containers that were calibrated to contain a particular volume of liquid is used to determine volume while sundials were used to tell how much time has passed by. There were plenty of strange unit of measurements back then.

But of course, not everyone have the same size of body parts to measure things efficiently. Say for example a person with a size 4 foot would measure distance very differently with a person whose shoe size is 9. Apart from the discrepancy of the shoe size, these two people would have very different length of their strut. These two things could affect the measurements severely. Now, in order to eliminate such problems, standardization of measurements is introduced. These measurements were developed and used universally for measuring length, distance, weight, temperature, electricity, etc.

There are two known system, one is the Metric System which uses the prefixes kilo-, centi-, deci- and milli- to express a particular unit of measurement, like kilogram, and centimeter and the other which is the Imperial Systems which is consisted of yards, miles, hectare, acre, foot, pounds, etc. They are used in different parts of the world, and some particular regions prefer the one of them over the other. In modern day, the International System of Units, SI is now more used. It’s simply the Metric System which is now adapted internationally in measuring a sorts of things in research, business and trade.

In this chapter, we will be looking into the two different system of measurement, specifically in session 1 and 2. We are also to understand the process of converting between these two systems in session 3 and learn how to convert between squares and cubic in session 4.

### Metric systems

Metric system, as known as International System of Units, is an internationally recognized system of measurement. Metric units are multiples of ten of the base unit. The three most common units in the metric system are the meter, gram and liter.