There are approximately 7.7 billion humans on Earth. If the virus spreads beyond the 200-person town, how long will it be until everyone on the planet is infected if the number of infected people doubles every week?

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.

Google it that might work