The states that control is enhanced by concentrating on the exceptions to, or significant deviations from, the expected result or standard.

The principle of exception is the managerial principle that states that control is enhanced by concentrating on the exceptions to, or significant deviations from, the expected result or standard.
This also refers to the fact that only what is important in a budget or a plan is shown to the manager, while the rest is excluded. 

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.