chart

A chart is a graphical representation of data designed to communicate information quickly and clearly. Charts use visual cues such as position, length, angle, and color to reveal patterns, trends, and relationships within a dataset. They are widely used in statistics, business, science, journalism, and education to summarize large amounts of information and aid interpretation and decision making.

Common chart types include bar charts, which compare quantities across different categories; line charts, which show changes over time; pie charts, which display proportions of a whole; histograms, which illustrate the distribution of numeric data; scatter plots, which reveal relationships between two variables; and area charts, which emphasize the magnitude of trends. Other formats such as bubble charts, stacked charts, and box plots serve specialized purposes in visualization practice.

The development of modern charts is associated with William Playfair, who in the late 18th and early 19th centuries introduced several standard forms, including the line graph and bar chart, and the pie chart in his Statistical Breviary (1801). With the rise of computers and data visualization software, charts have become more interactive and customizable, enabling features such as tooltips, filtering, and dynamic scaling.

Good chart design emphasizes clarity and accuracy. Desirable practices include clear titles, labeled axes or categories, properly scaled axes, and data sources. Avoiding misleading elements such as truncated axes or excessive decoration helps prevent misinterpretation. Accessibility considerations include color contrast and options for non-visual data interpretation.