This paper, the first of two, demonstrates why it is necessary for radiographers to understand basic statistical concepts both to assimilate the work of others and also in their own research work. As the emphasis on evidence-based practice increases, it will become more pressing for radiographers to be able to dissect other people's research and to contribute to research themselves. The different types of data that one can come across are covered here, as well as different ways to describe data. Furthermore, the statistical terminology and methods used that comprise descriptive statistics are explained, including levels of measurement, measures of central tendency (average), and dispersion (spread) and the concept of normal distribution. Th...