Bar Chart: Definition

Summary

• A bar chart visualizes discrete data with bars whose height is proportional to the values represented.
• Technical structure: horizontal axis for categories, vertical axis for measured values, uniform bar width
• Key difference from histogram: bar chart for discrete data vs. histogram for continuous data
• Step-by-step construction: organize the data, draw the axes with appropriate scales, draw the bars with corresponding heights.
• Available tools: free solutions (Miro, Canva), professional software (Excel, EdrawMax), ready-to-use templates
• Advanced applications: time animations, grouped bars for multiple comparisons, integration into real-time dashboards

What is a bar chart: definition and technical characteristics

A bar chart represents data in the form of bars. The heights of the bars are proportional to the values represented. This graphical tool compares discrete categories with each other.

The technical structure comprises two main axes. The horizontal axis indicates the categories being compared. The vertical axis represents a measured value. Each bar has a uniform width to facilitate reading.

The characteristics of the sticks follow specific rules:

• The height corresponds exactly to the value of the category.
• The spacing between the bars remains constant
• The bars can be vertical or horizontal.
• The width never changes between the sticks.

The difference between a bar chart and a histogram is fundamental. Bar charts deal with discrete data. Histograms are used for continuous data. This distinction guides the choice of the right graph.

Appropriate data types include:

• Qualitative variables (brands, countries, products)
• Discrete quantitative variables (number of sales, number of employees)
• Time categories (months, years, quarters)
• Age groups or shoe sizes

There are many applications within the company. Sales analysis by product becomes clear. Performance comparisons between teams are immediate. Presentations of results gain visual impact. Dashboards easily integrate these graphs to track key indicators.

How to build a bar chart step by step

Creating a bar chart requires a structured approach. This approach ensures clear and professional results.

• Identify and organize the digital data to be represented

Collect your data and sort it into categories. Make sure each value corresponds to a separate category. The data must be complete and consistent before you begin.

• Draw the horizontal axis: placement of categories and regular spacing

The horizontal axis displays your categories (months, products, regions). Divide the axis into equal segments according to the number of categories. Each segment should be the same width to avoid visual distortions.

• Draw the vertical axis: graduated scale proportional to the maximum values

The vertical axis displays the numerical scale. Start at zero and end slightly above your maximum value. Use regular intervals (10, 20, 50, 100) to make it easier to read.

• Constructing the sticks: height corresponding to the values, uniform width

Draw each bar from the horizontal axis to the corresponding height. The width remains the same for all bars. Leave a space between each bar to improve readability.

• Name the diagram and label the axes for clarity.

Add a descriptive title to the diagram. Clearly indicate what each axis represents with precise labels.

• Incorporate colors and patterns to improve readability

Use contrasting colors to distinguish between categories. Avoid visual effects that make it difficult to read the values.

Bar charts are a powerful tool for transforming raw data into strategic visualizations. Their simplicity allows businesses and professionals to communicate complex information quickly and effectively. Adopt this technique to improve understanding and decision-making in your data analysis.