Precision has to do with comparing a group of measurements and how close they all are in relation to each other. It is the relationships among a group of measurements of one item that defines the precision of those measurements. If a higher level of variation exists among a group of measurements, they are less precise. Precision is incredibly important in completing high-level measurement work because you need to rely on your tools to measure the same way for every use. Running a Gage R & R Study on your measurement system can clue you in to issues relating to precision. These data collection tests look at the repeatability and reproducibility of your system, making sure that each of these is precise in nature. Any issues that arise can then be looked into at both the machine and operator level.