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The most common naturally caffeinated beverages are coffee and tea, which in one form or another (usually served hot, but sometimes iced) feature in most world cultures. Other drinks are artificially caffeinated as part of their production process. These include certain soft drinks (primarily cola drinks), and also energy drinks designed as a stimulant, and to perpetuate activity at times when the user might ordinarily be asleep.
The consumption of caffeinated drinks is often intended entirely or partly for the physical and mental effects of caffeine. Examples include the consumption of tea or coffee with breakfast in many westernized societies, in order to 'wake oneself up', or the deliberate consumption of energy drinks by students wishing to study through the night, or revellers seeking to maintain an alert attitude during social recreation.Caffeine can cause a physical dependence, if consumed in excessive amounts. The need for caffeine can be identified when individuals feel headaches, fatigue and muscle pain 24 hours after their last energy drink. 
Many caffeinated drinks also have decaffeinated counterparts, for those who enjoy the taste, but wish to limit their caffeine intake because of its physical effects, or due to religious or medical perceptions of the drug and its effects.