Wolfram Research
Wolfram Math World: Population
MathWorld offers a number of related meanings for population in the realm of statistics.
Palomar Community College District
Palomar College: Principles of Population Growth
An excellent interactive review from Palomar College of population growth and how it can be described. Try out the interactive calculators of population size.
Rice University
Hyper Stat Online Statistics Textbook: Population
A definition of "population" as it refers to statistics.
Other
Catholic Culture: News: Mexico Population Becoming Elderly
A news article explaining how Mexico's population is expected to increase among elders and decrease in relation to children because fertility rates have decreased over the past 25 years.
University of Glasgow
Statistics Glossary: Target Population
Go to this site for a brief definition for what the target population of a sample is along with an example problem.