Histograms are a very common way to display data. Very similar to a bar graph (which is used for categorical data), but the bars may touch each other depending on the data.
To make a histogram:
You will need a vertical axis to represent the frequency and a horizontal axis to represent the values in your set of data. It is not a line plot where you simply put marks (dot or X) above the values.
The bars generally contain multiple values. A general rule in setting up your horizontal axis is to find the range (maximum value - minimum value) and divide by 7. We then round that value off to the nearest integer to determine our bin width. Hopefully this will allow us a good view of the data.
Occasionally you will need to make adjustments to your bin widths (spread of the bars) to get a better view. The values that go into each bar include the left side, but not the right. For example, if a bar starts at 2 and ends at 5, it will include all values greater than or equal to 2 and at the same time less than 5. Values of 5 will move into the next bar.