@fBoyle-- Competitive and comparative advantage are two ways of looking at manufacturing and trade.
Competitive advantage simply favors whoever manufactures a good at a lower price, sells more and makes the most profit. In a market where competitive advantage matters, the business that can accomplish this will dominate that industry and stifle all its competitors.
Comparative advantage is a more flexible system where everyone can produce something and trade with one another. It's a system where everyone is a winner because each business is encouraged to concentrate on the good that they have a better efficiency in. So a business (or a country) doesn't have to be the best at something, it can still participate in trade and benefit.