Short answers, pulled from the story.
The standard of living is the level of income, comforts and services available to an individual, community or society. This concept serves as a contributing factor to an individual's quality of life while generally focusing on objective metrics outside personal control.
An adequate standard of living was first described in the Universal Declaration of Human Rights. It was further described in the International Covenant on Economic, Social and Cultural Rights.
Research suggests ~15.3 GJ per capita by the end of the 21st century is achievable. Changes in technological efficiency and energy production and use allow for a Decent Living Standard for all people without fossil fuels.
Real income, disposable income, class disparity, and poverty rate form key metrics used by scholars. Gross domestic product, inflation rate, and national economic growth provide macroeconomic context alongside access to healthcare and education.
The idea of a standard may be contrasted with the quality of life, which takes into account not only the material standard of living but also other more intangible aspects that make up human life. Leisure, safety, cultural resources, social life, physical health, and environmental quality issues all factor into this broader concept.