Maria bought seven boxes. A week later
half of all her boxes were destroyed in a fire.
There are now only 22 boxes left. With
how many did she start?
Help??

The major difference is that a histogram is only used to plot the frequency of score occurrences in a continuous data set that has been divided into classes, called bins.  bar charts, on the other hand, can be used for a great deal of other types ofvariables  including  ordinal  andnominal  data sets.