A letter is a written message from one party to another containing information. Letters promote the preservation of communication between both parties; they may bring friends or relatives closer together, enrich professional relationships and provide a means of self-expression.

A house is a building that functions as a home, ranging from simple dwellings such as rudimentary huts of nomadic tribes and the improvised shacks in shantytowns to complex, fixed structures of wood, brick, concrete or other materials containing plumbing, ventilation and electrical systems.