"Visual literacy is a set of abilities that enables an individual to effectively find, interpret, evaluate, use, and create images and visual media. Visual literacy skills equip a learner to understand and analyze the contextual, cultural, ethical, aesthetic, intellectual, and technical components involved in the production and use of visual materials. A visually literate individual is both a critical consumer of visual media and a competent contributor to a body of shared knowledge and culture."
Visual rhetoric is the use of rhetorical theory as it relates to visuals and designs. Images and visual elements can be used to shape an argument - something to keep in mind when reading/viewing infographics, and when creating them.
Visual Rhetoric: Overview - more information on visual rhetoric from the Purdue Online Writing Lab
Because infographics are easy for nearly anyone to make, it is important to remain critical of the information they contain. Ask the same questions that you would of other sources, such as an article or website: