Auditory display is the presentation of information through sound. It involves translating data into sound that can be heard. There are different types of auditory display including audification, sonification, auditory icons, earcons, and spearcons. Principles of effective auditory display include compatibility, approximation, dissociability, parsimony, and invariance. Auditory display is best used for simple, short messages that require immediate action, while visual display is better for complex, long messages. Frequency, modulation, intensity, and separating warning sounds can improve auditory display effectiveness. An online hearing test is available from the hearing aid company ReSound.