Most geographers and demographers agree that over the course of the twenty-first century, the population growth will slow considerably. This is based on the belief that the current rapid population growth is an anomaly in Earth’s history and that the planet cannot sustain such rapid growth for another century.

Henry Ford invented the Model-T, the first mass-produced automobile. He also popularized the use of assembly lines and mass production. The concept of the assembly line, and the cheap mass production it provides, is closely associated with Ford to the point where it is sometimes called “Fordism.”

The natural increase rate does not consider immigration or emigration. It is determined by subtracting the number of deaths from the number of births in a given region. So, if there are ten thousand deaths and thirteen thousand births in a given region, in a given time period, the natural increase rate is three thousand.

Malthus’ “principle of population” states that eventually, population growth will exceed the capacity of agricultural production, which will lead to widespread starvation and suffering. Over the years, many detractors have proposed various arguments in opposition to Malthus’ theories. Two of the most prominent arguments are that a) population growth will slow due to the availability of contraception and the desire of governments to limit growth and b) technological innovation can lead to dramatic improvements in agricultural production, which allow it to keep up with the growth in population.

A population pyramid is used to show the percentage of the population who fit into various age groups. If a population pyramid is rectangular, that means the bottom section (where babies are represented), the middle section (where working adults are represented), and the top section (where older people who are often retired are represented) are roughly similar sizes. This generally means the population of a country is close to steady, but is possibly growing slightly. A country like Norway or the United Kingdom would have a rectangular population pyramid.

Henry Ford invented the Model-T, the first mass-produced automobile. He also popularized the use of assembly lines and mass production. The concept of the assembly line, and the cheap mass production it provides, is closely associated with Ford to the point where it is sometimes called “Fordism.”

The Industrial Revolution brought former farmers into the cities to work in factories. These farmers used to grow food for themselves and their families and now needed other ways to get food. Canning foods was a simple solution that made it possible for cities to have access to food.

During the past half-century much of the developed world has experienced a process known as deindustrialization -factories and manufacturing centers have closed down in the United States of America, Western Europe, and Japan and those jobs have been outsourced to the developing world. This has led to the rise of “service-based economies” in the developed world. A “service-based economy” is an economy in which most of the workers are involved in providing services such as research, marketing, telecommunications, innovation, teaching, and so on.

Physical Geography is one of the two major branches of geography. It studies the natural features of earth, as well as earth's natural processes. Physical Geography includes the study of mountains, geology, weather and climate, and much more. It looks at how the physical formation of the earth affects other aspects of geography. It does not directly deal with humans and social constructs — that is cultural or human geography.

Housing in urban centers was actually more expensive than housing in rural areas, due to the high value of land. Since cities are much more densely populated than rural areas, the competition for land is greater, driving up the cost of housing.