Classification is necessary for the organization of information because it allows everyone to refer to the same elements. In architecture, classification is made according to styles, and there are many of them. However, only hindsight (of time) makes it possible to specify and name this or that style of which you never really know when it begins, nor when it ends. For example, the first architects who "invented" Art Nouveau did not know whether this style would develop, how long it would last and what its distinctive elements would be. It didn't even have the name. The Art Deco style, clear and transparent for everyone today, was only given this name in the 60s. A style, even a breakthrough, is always the fruit of evolution and of diverse and varied inspirations, the result of crossbreeding.
In this site, we have tried to simplify as much as possible the styles that made up 20th Century architecture for greater clarity. Purists, art historians and architects may find our classification reductive and they may be right. However, simplification is good, for a site intended for all audiences.