On October 12, 1999, the Earth welcomed a newborn child that brought our planet's population up to the 6 billion mark, according to the U.N. Population Fund. While this is an astoundingly large number of people to have on the planet, what makes this figure even more remarkable is that as recent as 1960, there were only a little over 3 billion people on the planet. For the last century, we have been averaging a rate of increase in the world's population that would double it about every 50 years. If this continues, it means that we will have close to 12 billion people on the planet by the middle of this century. By some people's estimates, this would amount to complete environmental devastation if it were to happen.

While the world's population has been growing at a staggering pace, it has not been a universal growth. Stable, developed countries like those in Europe have not seen that much growth. In fact, some of these countries have actually experienced a decline in their population. Almost all of the growth has been in developing countries, where growth rates of more than 3% are not uncommon. Many of these countries with high growth rates are not even able to take care of the food, clothing, and housing needs of the citizens that they have right now.

In this module, we will investigate the basics of human population growth and our role in it.