In the past, people used different measuring units and there was no specified unit and since these units were not fixed and these vary from place to place therefore there was always a margin of error and people could never be sure that the readings, they are getting are exact. For example, previously people used cubit to measure the distance but this cubit was the distance from a man shoulder to nose. But since people have different physique and they have different width and height and therefore the measurement of this unit varies for every person.
As the time passed, people understood the importance of exact measurement and how it could benefit them in various calculations and how even a small error could be a reason of a huge loss. Then ISO introduced the standard units of measurement and these units were then implemented and followed across the world. After this, the units became fixed, the measurements became exact and now people had standard units to compare the values with. At this point, the importance of the calibration came. People made many instruments to measure different things. The market became full of manufacturer and each one of these manufacturers used the same units but different calibrations. Since these instruments needed to be checked every now and then to set the calibration and the task of calibrating an instrument required the expertise therefore the calibration companies came. These companies provided the calibration services to the industries and various labs and help the people working there in checking whether the instrument that they are using gives the exact reading as the standard one.
The calibration companies Melbourne need to have the approved and accredited instruments and devices by the NIST so that these could be used to calibrate other devices correctly. With the advent of the technology, not only have the instruments have gone advances but the devices which are used to calibrate these have also improved a great deal. The use of electricity and various sensors have made the calibration devices much more improved and now their output is much more accurate than it was ever before in the past. Not only are these correct but these are versatile calibrating devices which means that these can compare the readings of various devices which are placed on different location. This much of precision was never able to achieved in the past but now a days it is possible and happening in many places across the world.