Data frames

Many forms of data can be organized into data tables. Data tables are often called data frames.

A data table or data frame has rows and columns.

The rows may represent observations, such as people in a clinical trial, or sports teams. The columns represent variables - each variable is some type of information about the observations. For example, if the observations are people in a clinical trial, the variables might be age, height, weight and severity of disease. For a sports teams, they might be name, home city, number of games played, number games lost, won and drawn.

You can think of data frames as a sequence of columns of data, where each column has the values for one variable.