1. Line graphs - show the trend of a variable over time.

2. Bar graphs - compare the values of several variables. Often the values compared are frequencies or relative frequencies of outcomes of a nominal variable.

3. Scatter plots - graph bivariate data when both variables are measured in an interval/ratio or ordinal scale. Units for one variable are marked on the horizontal axis, and units for the other on the vertical axis.

Note: The independent variable should always go on the horizontal axis, and the dependent variable should go on the vertical axis when one of the variables is an independent and one a dependent variable.