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The most obvious visual difference between histograms and bar charts is in the way the rectangular bars are presented: in histograms, the bars touch, whereas bar charts have space separating each bar. But how do we know when to use each one?

#### Vocabulary

**What is a histogram?**

Shows the distribution of numerical data

X-axis consists of bins containing ranges of numbers

X-axis uses continuous numbers

Vertical bars touch each other

#### Further reading

I'm looking at a blog post on
the differences between histograms and
0:00

bar charts.
0:04

The blog post contains illustrations
reminding us how to tell them apart.
0:06

The most obvious visual difference
is in the way the rectangular bars
0:11

are presented.
0:15

In histograms the bars touch whereas bar
charts have space separating each bar.
0:16

But how do we know when to use each one?
0:22

The answer lies on the x-axis.
0:26

Bar charts visualize
discrete categories of data.
0:29

Let's say I'm coaching a basketball team.
0:33

I can use a bar chart to illustrate
each player's free throw percentage.
0:36

The order in which the data is
displayed can be reordered.
0:41

I could put the names alphabetically, or
0:44

from highest to lowest percentage,
depending on the story I want to tell.
0:46

Histograms, on the other hand,
0:52

show continuous data on the x-axis
using ranges of numbers.
0:54

We could present my players' free
throw percentage as a histogram,
0:58

if we visualize how many players make
between 50 to 60% of their free throws,
1:04

or 60 to 70, 70 to 80,
80 to 90, or 90 to 100%.
1:10

Each range of numbers on the x-axis
of a histogram is called a bin.
1:16

You'll notice that the bin labeled 70
to 80 is empty since none of my players
1:22

have a free throw percentage
within that range.
1:27

But I can't remove that bin from the
x-axis, otherwise my chart gets confusing.
1:30

I also can't reorder the bins.
1:36

The height of the rectangles in a
histogram represent the frequency of data
1:39

points in each bin.
1:43

Since 5 players hit between 80 and
90% of their free throws,
1:45

that's the tallest rectangle.
1:49

So let's review.
1:52

A histogram shows the distribution
of numerical data.
1:54

The x-axis on a histogram consists of
bins, containing ranges of numbers.
1:58

The x-axis uses continuous numbers,
2:04

meaning you can't rearrange them or
skip a bin.
2:07

And the vertical bars on
a histogram touch each other.
2:11

Hungry to learn more?
2:16

In our next video,
we'll take a look at the pie chart.
2:17

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