Which pair of points have equal x-coordinates? Opoints Q and R
O points Q and T
O points R and S
O points S and T

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.