**When you have finished this page,
try the Bar Graphs Quiz.**

**Bar graphs are an excellent way to
show results that are one time, that aren't continuous - especially samplings
such as surveys, inventories, etc. Below is a typical survey asking students
about their favorite after school activity. Notice that in this graph each column
is labeled - it is also possible to label the category to the left of the bar.
**

**In this case, the numbers for each
category are across the bottom of the chart. **

**A bar chart is marked off with a
series of lines called grid lines. These lines typically mark off a numerical
point in the series of numbers on the axis or line. In this case, each grid
line going up and down marks a multiple of 20 as the graph is divided such.More
gridlines can make it easier to be exact with the amounts being shown on the
bar graph, but too many can make it confusing.**

**Notice that for data that does not
fall evenly on a multiple of 20, the bar is in between two grid lines. **

**Bar graphs are useful to get an overall
idea of trends in responses - which categories get many versus few responses.
**

Activity |
Number |

Visit
W/Friends |
175 |

Talk on
Phone |
168 |

Play Sports |
120 |

Earn Money |
120 |

Use Computers |
65 |

**
**

**
**