metric has a name for every multiple of ten so if you know the base unit you can use it anyway you want. for a meter it would go a decimeter, centimeter, millimeter. there are more but as you can see decimeter isnt really used but deci is also what is used for bels aka a decibel, this applies to all metric units so instead of memorising random conversions between a few things you know all the conversions based off of the prefix and unit edit: didnt see the link that you posted just the poll