graphic, graphics, graphical

As a noun, use graphic to refer to a picture, display, chart, or other visual representation.

Use graphics to refer in general to pictures, displays, charts, and other visual representations using computers. For example, graphics software.

Most of the time, use graphical as an adjective. Use graphic as an adjective only to mean vivid or realistic or in the phrase graphic arts.

Examples
To import a graphic from another file, select Picture.
Select the graphics file you want to open.
The image is graphic and accurate.
This course provides graphic design basics.
The graphical UI simulates a coliseum.