A histogram is suitable for interval or ratio data, where the horizontal axis represents data X and the vertical axis represents frequency f. The distribution of frequency is represented by the histogram between the data. The height of the histogram represents frequencies, and the width represents the exact interval.

When the data is a nominal or ordinal scale, a bar graph is used to represent the degree distribution, leaving a certain space between each histogram.

A line graph, also known as a frequency distribution polygon, is suitable for interval or ratio data. It connects the frequency points corresponding to each X value into a line and represents the trend of data changes with lines.

A stem and leaf display represents a large amount of data without using a grouped frequency tables.

Stem and leaf display is generally not used in formal report.