Fun is the enjoyment of pleasure and, according to Johan Huizinga, "an absolutely primary category of life, familiar to everybody at a glance right down to the animal level."Fun may be encountered in many human activities during work, social functions, recreation and play, and even seemingly mundane activities of daily living. Fun may often have little to no logical basis, and opinions on whether or not an activity is fun may differ. The distinction between enjoyment and fun is difficult to articulate but real, fun being a more spontaneous, playful, or active event. The perception of time is shortened when one is "having fun".