A millimetre is a unit of length commonly used in the metric system, abbreviated as mm. It is derived from the base unit of length in the International System of Units (SI), the metre (m). Specifically, a millimetre is equal to one thousandth (1/1000) of a metre, making it a very small unit of measurement.
The millimetre is primarily used to measure objects or distances that are relatively small, for example, the thickness or width of a paper, the dimensions of electronic components, or even the size of certain insects. Due to its small scale, millimetres are often used in precision engineering, manufacturing, construction, and scientific fields where accuracy is crucial.
The millimetre is based on the decimal system, which makes conversions to other metric units straightforward. For instance, one metre equals 1,000 millimetres, and one centimetre is equivalent to 10 millimetres. On the other hand, converting to larger units involves dividing the length by 1000. It is worth noting that the millimetre is also commonly used along with larger metric units such as the centimetre, decimetre, and kilometer, for more convenient measurements. In certain industries like automotive engineering or aerospace, tolerance measurements are made in micrometres (μm), which are a thousand times smaller than a millimetre.
