To represent data in a more organized and structural manner, graphs have been proven to be the best option. It has edges and vertices connecting them.

And the visual representations of it are known as charts.

It is used in various subjects that include maths, physics, chemistry, etc. graphs and charts have types that are used according to the data that has to be represented.

These types include Histogram and Bar-graph. Both of them have different characteristics that are important to understand for using them.

**Bar Chart vs Histogram**

The difference between Bar Chart and Histogram is that histogram represents the frequency distribution of non-discrete series of variables, whereas the bar chart represents the comparison of discrete variables. Both of them are also different as bars in histograms are connected and may have different widths, whereas bars in bar charts are not connected and generally have the same width. They also differ in terms of dimensions and rearrangement of blocks. Last but not least, the histogram is used for numerical data, while the bar chart is used for categorical data.

A Bar Chart is used for representing the data in pictorial form. It mostly represents the grouped data in a rectangular shape. It is also called a bar graph.

It is the basic form of pictorial representation of data used mostly in statistics. It is a one-dimensional representation. It also has several types and categories.

The histogram represents the continuous class of grouped frequency distribution in graphs.

It has rectangles that are adjacent and are proportional to the frequency of a variable, and have the same width as the class intervals. It is a two-dimensional representation.

It is the most used for frequency distribution. There are several types of histogram graphs that are used based on preference mostly.

**Comparison Table **

Parameters of Comparison | Bar Chart | Histogram |
---|---|---|

Variables | Comparison of discrete variables. | Distribution of non-discrete variables. |

Bars | Does not touch each other | Touch each other |

Width | Mostly equal | May vary. |

Dimensions | One dimensional | Two dimensional |

Types of data | Categorical data. | Numerical data. |

**What is Bar Chart?**

It is used for representing the grouped data and statistics in the form of a picture (rectangles). Following are the properties of a bar graph.

- All rectangles have a common base, and these rectangles are called bars.
- Columns of each should have equal width.
- The height of the bars represents the value.
- Distance between bars or rectangles should be equal.

Advantages of Bar Chart:

- Summarises the large data.
- Frequency distribution is displayed with each class.
- Clarifies it better than tabular form.
- Helpful in estimating the key values.

Disadvantages of Bar Chart:

- It may not reveal the pattern and cause, etc.
- It can be easily manipulated.

Types of Bar Charts:

- Vertical Bar Graphs: bars are represented in a vertical form where bars are used for representing the measure of data. The bars are represented on the y-axis, and its height represents the values.
- Horizontal Bar Graphs: when the bars are drawn horizontally on the x-axis, they show the measures of data, and the length of them is representing the values of data.
- Grouped Bar Graphs: they are called cluster bar graphs. It is used for representing more than one object of the same categories, with discrete values. In this, different sets of items are compared.
- Stacked Bar Graphs: also known as composite bar graphs, in this each bar can be described with different colors to make t easy for the comparison, bars of this bar represent different groups.

**What is Histogram?**

It is a graphical representation of frequency distribution. Following are the steps required for constructing a histogram:

- Mark the X-axis and Y-axis by class intervals and frequencies, respectively.
- The scale should be the same for both axes’.
- Class intervals should be exclusive.
- Draw rectangles as per the data.

Use of histogram can be done under the following circumstances:

- Data is organized in numerical.
- To check the shape of data distribution.
- In the case of two or more processes for checking, the output is different.
- To check whether the process is meeting the customer requirements.

Following are the types of the histogram:

- Uniform Histogram: it reversals that the number of classes is extra small. And in this, each class is having the same number of elements. It may or may not have distribution with several peaks.
- Bimodal Histogram: bimodal histogram has two peaks. It is used for the data that has two different kinds of individuals or groups.
- Symmetric Histogram: it has the same shape on both either sides of the middle. It is perfectly symmetric, which means it is cut in half. Both of the halves will look like a mirror image. Those who are not symmetric are called skewed.
- Probability Histogram: it is used for showing the pictorial representation of discrete probability distribution. It is begun by selecting the classes.

**Main Differences Between Bar Chart and Histogram**

- Both histogram and bar chart is used for pictorial representation of the different types of data, bar chart mainly used for comparing the discrete variable while the histogram is used for the representation of the distribution of a non-discrete variable.
- Both types have rectangular-shaped bars, but in the bar chart, the bars do not touch each other, whereas in the histogram, each bar connects or they touch each other always, leaving no space in between.
- In the histogram, elements are grouped to make them considered as ranges, but this is not the same in the bar chart. Elements are taken as individuals only.
- The width of the bar chart is almost the same, whereas, in Histogram, the width may or may not vary.
- A bar chart is used for comparing the different data of different categories, whereas a histogram is used for displaying the occurred frequencies.
- The rearranging of blocks cannot be done in histograms, while it can be done in bar charts.

**References **

- https://ieeexplore.ieee.org/abstract/document/6875990/
- https://ieeexplore.ieee.org/abstract/document/4275059/
- https://www.tandfonline.com/doi/abs/10.1080/10691898.2014.11889701

I am Sandeep Bhandari; I have 20 years of experience in the technology field. I have various technical skills and knowledge in database systems, computer networks, and programming. You can read more about me on my bio page.