A
sock is a knitted garment for enclosing the human foot.
The word sock comes from the Latin word
soccus, which was a type of low-heeled loose-fitting shoe or slipper, used by the Greeks and also by Roman comedians. It then passed through Old English
socc and Middle English
socke. The Latin word may have derived from the ancient Greek
sukkhos which was a Phrygian shoe. This word was probably derived from an Asian language. Some of the Greeks wore their
soccuses on their feet, then put their sandals on top on them, and like modern day people they took their sandals off and walked around in their houses in their
soccuses
A
slipper, also called houseshoe, is a soft and lightweight indoor type of footwear.
The word is recorded in English in 1478, deriving from the much older verb to slip, the notion being of footware that is "slipped" onto the foot.
The modern slipper has evolved from those first made in Japan during the Meiji period. The Japanese were accustomed to taking off their shoes before rising into their homes (as was not the case for most cultures at the time.) The Meiji period saw many foreigners being brought to Japan from all over the world for various purposes, mainly trade. The Japanese saw it a problem that these foreigners did not know their customs and entered indoors with their shoes on. Thus, they invented slippers for the foreigners to use as a cover over the shoes as to keep the indoors sanitary.
Source: Wikipedia
