No matter how much care is taken during an experiment, or how sophisticated the equipment used, values obtained through measurement are influenced by errors. Errors can be thought of as acting to conceal the true value of the quantity sought through experiment. Random errors cause values obtained through measurement to occur above and below the true value. This chapter considers statistically-based methods for dealing with variability in experimental data such as that caused by random errors. As statistics can be described as the science of assembling, organising and interpreting numerical data, it is an ideal tool for assisting in the analysis of experimental data.