### 5.1 Preparation of Data Files

Before analysis can commence, the data must be loaded into pspp and arranged such that both pspp and humans can understand what the data represents. There are two aspects of data:

- The variables — these are the parameters of a quantity which has been measured or estimated in some way. For example height, weight and geographic location are all variables.
- The observations (also called `cases') of the variables — each observation represents an instance when the variables were measured or observed.

For example, a data set which has the variables height, weight, and name, might have the observations:

         1881 89.2 Ahmed
         1192 107.01 Frank
         1230 67 Julie

The following sections explain how to define a dataset.