What is the best chart for comparing categories?

A sorted bar chart. Horizontal bars make long labels easy to read.

When should I use a pie chart?

Rarely: only for two or three parts of a whole where the exact values do not matter. A bar chart is almost always clearer.

Is Tableau good for data visualization?

Yes. It is one of the most widely used tools for it, and Tableau Public lets you practice for free.

What is data visualization?

Business intelligence glossary Business intelligence courses

Quick answer

Data visualization is showing data as charts, maps or tables designed so that a pattern, comparison or change is obvious at a glance: bars to compare, lines for change over time, maps for places.

Last updated October 22, 2026

Updated October 22, 2026 · By Robert Breen

Why it matters

People spot a dip in a line chart in a second, but they can stare at a table of 52 weekly numbers and miss it. Good visualization moves the work from reading to seeing.

The chart type is the main decision. Most business questions are covered by four: bar (compare categories), line (change over time), scatter (the relationship between two numbers) and a plain table with highlighting (exact values).

A worked example

A finance team wants to show monthly operating expenses for the year. As a table, the 12 numbers range from $182,000 to $241,000 with no obvious story. As a line chart, there is a clear jump in April that never comes back down, which turns out to be a new office lease.

The same data as a pie chart with 12 slices would hide the jump completely, because pie charts show share of a total, not change over time.

Often confused with

Data visualization vs dashboard

A visualization is one chart. A dashboard arranges several charts and filters on one screen.

Data visualization vs infographic

An infographic is a designed, mostly static graphic that tells one story, often for marketing. BI visualizations are tied to live data and meant for analysis.

Data visualization vs AI-generated charts

Assistants such as ChatGPT can now draw a chart from a spreadsheet you upload. That is handy for a first look, but a BI chart stays connected to the source and refreshes.

Tips

Start bar axes at zero; truncated bars exaggerate differences.
Use color to highlight one thing, not to decorate.
Title the chart with the takeaway ("Expenses stepped up in April"), not just the field names.

Dashboard Dimension Measure Business intelligence (BI)

Learn it in a free lesson

Tableau Public Tutorial: Your First Chart and Dashboard (about 15 minutes)

Frequently asked questions

What is the best chart for comparing categories?: A sorted bar chart. Horizontal bars make long labels easy to read.
When should I use a pie chart?: Rarely: only for two or three parts of a whole where the exact values do not matter. A bar chart is almost always clearer.
Is Tableau good for data visualization?: Yes. It is one of the most widely used tools for it, and Tableau Public lets you practice for free.

All business intelligence terms, A to Z · Free business intelligence lessons