I recently purchased a bag of Plain M&Ms. The M&M's
were in six different colors. A quick count showed that there
were

Color | Frequency |
---|---|

Brown | 17 |

Red | 18 |

Yellow | 7 |

Green | 7 |

Blue | 2 |

Orange | 4 |

This table is called a frequency table and it describes the distribution of M&M color frequencies. Not surprisingly, this kind of table is called a frequency distribution. Often a frequency distribution is shown graphically as in Figure 1.

The distribution shown in Figure 1
concerns just my one bag of M&M's. You might be wondering
about the distribution of colors for all M&M's. The
manufacturer of M&M's provides some information about this
matter, but they do not tell us exactly how many M&M's of
each color they have ever produced. Instead, they report
proportions rather than frequencies. Figure 2 shows these proportions. Since every M&M is
one of the six familiar colors, the six proportions shown in
the figure add to one. We call Figure 2 a probability distribution because
if you chose an M&M at random, the probability of getting,
say, a brown M&M is equal to the proportion of M&M's
that are brown (

Notice that the distributions in Figure 1 and Figure 2 are not
identical. Figure 1 portrays the
distribution in a sample of