Takt time, derived from the German word Taktzeit, translated best as meter, is the average unit production time needed to meet customer demand. For example the customer wants to buy 10 units per week, the average time to build an unit must be 4 hours (or less) if the units are built during a 40 hour work week. Industrial manufacturing lines must have production cycle times at least as short as the takt time so that production can meet the customer demand. This production 'cycle time' should be less than or equal to Takt time. For example, in automobile manufacturing, cars are assembled on a line, at a certain cycle time, ideally being moved on to the next station within the takt time so as to neither over or under produce. The cycle time to complete work on each station is often less than the takt time in order to ensure that the customer is never short of product. Although theoretically you want to match cycle time to takt time to avoid building inventories and over-sizing equipment, the reality is that demand is dynamic and never precisely known and also process disruptions such as unplanned downtime can occur. Thus, in practice, it is generally understood that cycle time needs to be slightly less than takt time.