Title: Images, Charts and Graphs Accessibility Basics
Course: Web Accessibility MOOC for Educators > Section: Creating Accessible Images, Diagrams, and Charts

Images, charts, graphs, and other complex images often require extensive description to be made accessible to users who are blind or have visual impairments. A complete equivalent text description is usually too long to be included in an alt tag attribute.

There are two approaches that can provide a textual equivalent of the image, chart or graph.

1. Provide a longdesc attribute, which can also be a link to an external file containing a lengthier description of the image, chart or graph.
2. Alternately the textual description can be provided inline on the same page near the chart or graph.

If you are working with charts and graphs, it is crucial to the content of understanding the page the chart or graph is located in, you must provide a text description of the chart or graph. Ideally, for charts or graphics the equivalent would include an accessible data table in HTML that contains the same data in tabular format. Providing a tabular format in addition to summary information about the chart or graph will allow users to review the data points themselves while still having the benefit of an overview summary of data.