In summary
Bar Charts and Histograms are used for two different purposes. Bar charts measure qualities; histograms measure quantities.
Bar charts should be used to explain how much stuff there is in different categories, and categories are qualitative. So, what do I mean by "categories" or "qualtitiave"? I mean things like Toyota cars, Honda cars. "Toyota" is a quality because "Toyota" is not based on a number. (Explained in detail with bar chart below)
Histograms tell how you how much stuff is associated with numeric ranges (more ) . For instance, imagine a class took a quiz, and you wanted to display how many students scored between a 90-100, and a 80-89, 70-79, 60-69. In this case, the you are measure a numeric quantity like 90-100. We call this quantitative data. Read on to better understand the differences in this two types of charts that look similar but are not interchangeable.
When to use bar charts
Answer:It's about "quality"
![when to use bar charts](images/when-to-use-bar-charts.png)
A Second
example of a Bar Chart
Bar charts are used to show how much "stuff" different categories have. Imagine, for instance, if you ask all of the students in your grade to choose a favorite color. And 40 chose green, 33 chose orange, 25 chose yellow and 15 chose blue. This is not a situation for a histogram (as you'll see if you read onwards). Instead, you should create a bar chart like the one below
![example of a bar chart](images/example-of-bar-chart-favorite-colors.png)
What went wrong ?
Imagine you want to display the grades of students in your math class of 20 kids. In our class,; 10 kids got How many kids got A's? If we wanted to show how many students earned A's, how many earned B's, C's, D's and F's, then you want to use..... a Bar chart! Bar Charts are good at showing, as we wrote earlier, how much "stuff" is there. In this case, the "stuff" is A's, then it's B's, C's. An "A" is a category and the technical terms is that an "A" is qualitative. In other words, an A is not a number. It's a group, a category. How many scored between a 70 and 79? On the other hand, if you wanted to depict how many kids got scores in the range of 100-90, 80-89, 70-79, 60-69, then you would use a histogram like Graph 2 below, and each "bar" would represent how many scores are in the intervals. If there were 10 A's, then we would have a 10 for the interval 90-100. These intervals, since they are always based on numbers are known as "quantitative" data, data based on numbers.![Example of a histogram](images/example-of-histogram.png)