If a minute hand on a clock is at 1 hour would that be an angle

To have an angle, there must be TWO line segments. You stated that there is only one clock hand.

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.