In linguistics, the comparative method is a technique for studying the development of languages by performing a feature-by-feature comparison of two or more languages with common descent from a shared ancestor, as opposed to the method of internal reconstruction, which analyzes the internal development of a single language over time.

The Peace Corps is a volunteer program run by the United States government. The stated mission of the Peace Corps includes three goals: providing technical assistance; helping people outside the United States to understand American culture; and helping Americans to understand the cultures of other countries.

On this date in 1776, rebellious colonials launched the first modern democracy, an experiment in government controlled by the people themselves. America succeeded so well that virtually the entire world later adopted democracy with its guarantee of personal rights.

Los Angeles County Immunization Program efforts are targeted primarily toward pediatric and adolescent immunizations , with some adult immunization activities. Although this Program serves the entire County population, many activities are specifically directed toward communities with children at high risk of under-immunization. The Immunization Program partners with other organizations to provide outreach and immunization services in pockets of need areas , which are defined as those areas with large numbers of un-immunized and under-immunized children.

Endemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. The extreme opposite of endemism is cosmopolitan distribution.