Availability bias, also known as the availability heuristic, is a cognitive bias in which people rely too heavily on information or examples that are more easily recalled from memory when estimating the frequency, likelihood, or risk of an event. If instances of an event come to mind more readily, individuals tend to believe that the event occurs more frequently or is more likely to happen. While this mental shortcut allows for quick decision-making, it often leads to inaccurate assessments of reality—because the vividness, recency, or emotional impact of a memory does not necessarily correlate with the actual frequency of the event.