http://www.dreamhomedesignusa.com/    Architectural styles vary by country, culture, region and political events.  Materials and labor also contribute to a style whether historic, national, or vernacular.  Traditional styles have many years in development.  They can be based on theory or practical construction techniques.  Here see a European French inspired design and the contrast between a Southwest Contemporary design that takes the vernacular style of adobe and even some Spanish Mediterranean cues.  The Euro style has steeper roofs and historic elements that derive from Greek and Roman temples.  The steeper roof actually has a base in tax code in France!  Please post your comments.