This is a short introduction to information visualisation, which is increasingly important in many fields as information expands faster than our ability to comprehend it. Visualisation makes data easier to understand through direct sensory experience (usually visual), as opposed to more linguistic/logical reasoning. This chapter examines reasons for using information visualisation both for professional data analysts and also end-users. It will also look at some of the history of visualisation (going back 4,500 years), classic examples of information visualisations, and some current challenges for visualisation research and practice. Design of effective visualisation requires an appreciation of human perceptual, cognitive and also organisational and social factors, and the chapter discusses some of these factors and the design issues and principles arising from them.