primary sector - the production or extraction of raw materials

secondary sector - the manufacture of goods, e.g. cloth from cotton

tertiary sector - providing services to people, e.g. a doctor

quaternary sector - knowledge-based industries or high-tech industries

counter-urbanisation - the movement of people to rural areas from urban ones

natural increase - growth of the population due to increased birth rate

greenbelt -  space around cities for which there are strict planning controls

commuter - someone that has to travel to work regularly

Positive economic impact - shops and services benefit from increased footfall

Negative economic impact - competition for houses raises prices making them unaffordable

Positive social impact - opportunity for more diversity in the community

Negative social impact - potential for poor community cohesion between locals and newcomers