A bar histogram, commonly referred to as a bar chart or bar graph, is a type of data visualization used to represent categorical or discrete data. It is used to display data in rectangular bars or columns, where the length or height of each bar is proportional to the frequency or count of the categories being represented. Bar histograms are often used to visualize data distribution, compare classes, or show the frequency of occurrence for different groups or values.

Key characteristics and uses of bar histograms include:

- Categorical data representation: Bar histograms are primarily used to display categorical or discrete data, where the data points fall into distinct categories or groups.
- Frequency display: The height of each bar in a bar histogram represents the frequency or count of data points within a specific category. The taller the bar, the more frequently the category appears in the dataset.
- Comparisons: Bar histograms help compare different categories or groups, making them valuable for visualizing comparisons, trends, or disparities.
- Data distribution: They provide insight into data distribution. For instance, you can see whether a distribution is skewed, symmetric, or bimodal by examining the shape of the bars.
- Data summarization: Bar histograms offer a concise way to summarize data, making it easy to communicate information to a broader audience.
- Data exploration: They are often used in exploratory data analysis for quickly overviewing a dataset and identifying patterns and anomalies.

While bar histograms are excellent for categorical data, to represent continuous data, one should use a different type of chart, such as a histogram, which displays the distribution of continuous data by dividing it into intervals (bins) and counting the number of data points in each interval.

## List of recommended resources #

### For a broad overview #

A Complete Guide to Histograms

This data tutorial guide to histograms by Chartip provides a broad overview of histograms, a type of chart that plots the distribution of values.

This webpage by Stat Trek gives a general understanding of histograms and bar charts used in data visualization.

### For in depth understanding #

Data Visualisation: A Handbook for Data Driven Design

This book by Andy Kirk gives an extensive understanding of various data visualization techniques, providing a step-by-step thorough explanation.

Effective Data Visualization: The Right Chart for the Right Data

Written by Stephanie D. H. Evergreen, this comprehensive how-to guide shows readers how to create Excel charts and graphs that best communicate their data findings

### Case study #

An HCI survey on elderly users in India

This paper by Pradipta Biswas and Pat Langdon uses a histogram to present the various age groups in India and studies the human-computer interaction (HCI) among its users.

Data Mining with Histograms – A Case Study

This conference paper by Jan Rauch and Milan Simunek introduces histograms as an interesting tool for data mining and describes an application of the procedure CF-Miner mining for various types of histograms.

## References #

Data Visualization Resources: Types of Charts and Graphs for Data Viz