How do i analyse histograms/frequency density graphs?

Question

i need to compare 2 of them by analysing them

Answer 1

Here's the way I understand the question:
A histogram is a plot of discrete (counts) data; each bar representing a probability of that particular count.
A frequency density graph is a plot of continuous data. The probability of a particular point is 0 and probabilities are found for intervals.
I don't know how you would compare the two -- they represent 2 different types of data. I suppose you could find the mean and standard deviation of each, but there is no statistical test (that I know of) to compare the two.

Answer 2

Understanding Histograms:

http://www.luminous-landscape.com/tutorials/understanding-series/understanding-histograms.shtml

Answer 3

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