Coffee is one of the world's most popular beverages, and citizens of Sweden lead the world in the per capita consumption of coffee. Coffee contains caffeine, a substance that interferes with sleep. Muslims who drank it to stay awake during their long religious rites were criticized by their priests.
Students studying for examinations sometimes drink coffee to stay awake.
Many people who drink coffee do so simply because they like it. One of the main problems in the expansion of education is to avoid sacrificing quality for quantity. Individuals involved in teaching must be of the highest merit. Good intentions alone will not be of any significant value. Because there were so many different native tribes in North and South America, anthropologists have found it necessary to group the tribes for purposes of study.