ABSTRACT
Sleep is one of man’s primary needs and to sleep in security one of his most legitimate desires. Consequently for refuge against inclement weather, against wild beasts and other men, he seeks a shelter where he can rest undisturbed. According to his environment, these shelters are of different kinds, and it is impossible to say which kind was used first. The kind depends principally on the climate and the surroundings. If we try to classify the habitations which man has used, we must consider in turn those which nature offered him, and then those which he himself constructed, and then among the latter distinguish between those which were fixed and those which could be transported.
