What is Data Visualization?
Data visualization is presenting data as charts, maps and other graphics so that patterns and outliers are easy to see.
Data Visualization explained
A good chart choice follows the question: lines for change over time, bars for comparing categories, scatter plots for relationships between two measures.
Visualisation can also mislead: truncated axes, too many colours and cumulative charts that hide a decline are common culprits. Showing the underlying numbers beside a chart helps readers check it.
Example
A line chart of weekly orders with last year's line behind it shows seasonality at a glance.