**Length** - **m**, **dm**, **cm**, **mm**, **micrometre**

**Length**refers to the shortest distance between to points.

**m**is the abbreviation for metre (**m**is an SI unit for length) (more)

**d**placed before other abbreviations is an abbreviation for**deci-**, which means one tenth (1/10).

Therefore 1**decimetre**(**dm**) is 1/10 of a**m**or 10**cm**= 1**dm**

**c**placed before other abbreviations is an abbreviation for**centi-**, which means one hundredth (1/100).

Therefore 1**centimetre**(**cm**) is 1/100 of a**m**or 100**cm**= 1**m**

**m**placed before other abbreviations is an abbreviation for**milli**-, which means one thousandth (1/1000).

Therefore 1000**millimeters**(**mm**) = 1**m**

or 100**mm**= 1**cm**

is an abbreviation for*µ***micro**and means on millionth (1/1,000,000)

Therefore 1,000,000**micrometres**() = 1*µm***m**(**metre**)

Or 10,000**micrometres**() = 1*µm***cm**(**centimetre**)

Or 1,000**micrometres**() = 1*µm***mm**(**millimeter**)

The term**micron**is used interchangeably with the term**micrometre**, however, it is now designated an obsolete term.

A**micro**__meter__is an instrument capable of measuring**micrometers**