Americanization is the a term used for the influence the United States of America has on the culture of other countries, substituing local culture with something of an American culture. It is often used in a negative context.
One of the principal reasons for this is America's highly visible global brands (e.g., McDonald's) and widely distributed media output.
It is often used as a term for fears of cultural substitution and can be compared to American fears of America being changed to be more like Mexico.
