Flags of All Countries
NAVA - North American Vexillological Association
A non-profit organization dedicated to the scholarly study of flags and flag history.
the Flag of the United States of America
(Despite a trend towards changing current Social mores (MORE-rays), there is a proper way to display this Nation's colors and this site is an excellent place to learn how to do so...even if you think you already know.)
The World Flag Database
There are over 260 pages on countries and international organizations. Each page contains basic information on the country, including its formal name, capital city, area, population, currency, languages, and religions.