In 2007. Friendly communities first appeared in the 2007 World Health Organization's Guide to the Construction of Global Elder Friendly Cities. Starting from eight key areas, the Guide proposes for the first time to build an elderly-friendly city from both hardware and software. Community is a large group of social groups or social organizations that gather in a certain field and are interrelated in life. It is the most basic content of social organism and the epitome of macro-society.