1. Modern architecture
Modern architecture is a term applied to an overarching movement and period in architectural history during the 20th century, with its exact definition and scope varying widely.
In one of the broader meanings, as will be used here, modern architecture began at the turn of the 20th century with efforts to reconcile the principles underlying architectural design with rapid technological advancement and the modernization of society.
When compared to that which preceded it, modernism in architecture is broadly characterized by simplification of form and subtraction of ornament from the structure and theme of the building.

2. MODERN/INTERNATIONAL STYLE ARCHITECTURE
architectural modernism was adopted by many influential architects and architectural educators, and continues as a dominant architectural philosophy for institutional and corporate buildings into the 21st century.
Modernism eventually sparked movements critical of it, most notably Postmodernism
Notable architects important to the history and development of the modernist movement include Frank Lloyd Wright, Ludwig Mies van der Rohe, Le Corbusier, Alvar Aalto, Walter Gropius and Louis I Kahn.

3. Characteristics Common themes of modern architecture include:
the notion that "Form follows function",
simplicity and clarity of forms and elimination of "unnecessary detail"
visual expression of structure (as opposed to the hiding of structural elements)
the related concept of "Truth to materials", meaning that the true nature or natural appearance of a material ought to be seen rather than concealed or altered to represent something else
use of industrially-produced materials; adoption of the machine aesthetic
particularly in International Style modernism, a visual emphasis on horizontal and vertical lines

4. Origins
The Crystal Palace, 1851, was one of the first buildings to have vast amounts of glass supported by structural metal, foreshadowing trends in Modernist architecture.
Others see Modern architecture as primarily driven by technological and engineering developments
Still other historians regard Modernism as a matter of taste, a reaction against eclecticism and the lavish stylistic excesses of Victorian and Edwardian architecture.

5. Advances in building technology
With the Industrial Revolution, the availability of newly-available building materials such as iron, steel, and sheet glass drove the invention of new building techniques
A further development was that of the steel-framed skyscraper in Chicago around 1890 by William Le Baron Jenney and Louis Sullivan.

6. Early years
Around 1900 a number of architects and designers around the world began developing new solutions to integrate traditional precedents (classicism or Gothic, for instance) with new technological possibilities.
The work of Louis Sullivan and Frank Lloyd Wright in Chicago, among many others, can be seen as a common struggle between old and new.

7. In the United States
Following out of the experiments in Art Nouveau and its related movements around the world, modernism in architecture and design grew out of threads originating in several different regions of the world:
the Robie House (1910) in Chicago, Illinois were some of the first examples of modern architecture in the United States
The Robie House, 1910, in Chicago, Illinois.

8. In Italy: Futurism
Futurist architecture began in the early-20th century, characterized by anti-historicism and long horizontal lines suggesting speed, motion and urgency.
Technology and even violence were among the themes of the Futurists.

9. In Italy: Futurism
Futurist architecture began in the early-20th century, characterized by anti-historicism and long horizontal lines suggesting speed, motion and urgency.
Technology and even violence were among the themes of the Futurists.
The unbuilt designs and theories of Futurists would go on to influence the Constructivists.

10. In Russia: Constructivism
Following the 1917 revolutions in Russia, the societal upheaval and change was coupled with a desire for a new aesthetic, one more in keeping with the Communist philosophy and societal goals of the new state, in contrast to the ornate Neoclassicism that had prevailed prior.
This resulted in a new style, Constructivism.

11. The AEG Turbinenfabrik ("turbine factory"), 1909, designed by Peter Behrens, illustrating the combination of industry and design.
In Western Europe
Spanning the gap between the ideals of the Arts and Crafts movement, and the Modernism of the 1920s, was the Deutscher Werkbund (German Work Federation) a German association of architects, designers and industrialists.

12. The Second Goetheanum, , in Basel, Switzerland, is an example of architectural Expressionism.
Expressionism
Expressionism was an architectural movement that developed in Northern Europe during the first decades of the 20th century in parallel with the expressionist visual and performing arts.
Making notable use of sculptural forms and the novel use of concrete as artistic elements.
The style was characterised by an early-modernist adoption of novel materials, formal innovation, and very unusual massing, sometimes inspired by natural biomorphic forms, sometimes by the new technical possibilities offered by the mass production of brick, steel and especially glass.

13. The Bauhaus building at Dessau, designed by Walter Gropius
Main articles: New Objectivity (architecture) and Bauhaus
Rise of Modernism
It was at this time, during the 1920s, that the most important figures in Modern architecture established their reputations.
The big three are commonly recognized as
Le Corbusier in France,
and Walter Gropius
Ludwig Mies van der Rohe in Germany,
of whom trained under Peter Behrens.

14. Style Modern: tradition and modernism
Following WWI, a stylistic movement would develop that embraced ideas of both modernism (or at least modernization) and traditionalism.
It is characterized by the adoption of the machine aesthetic, glorification of technological advancement and new materials, while at the same time adopting or loosely retaining revivalist forms and motifs, and the continued use of ornament.
A later variant, Streamline Moderne, simultaneously both played a role in industrial design and borrowed forms from machines themselves.
Greyhound Bus Station in Cleveland, Ohio, showing the Streamline Moderne aesthetic.

15. Wartime innovation Quonset hut en route to Japan
World War II (1939–1945) and its aftermath was a major factor in driving innovation in building technology, and in turn, architectural possibilities.
The wartime industrial demands resulting in a supply shortage (of such things as steel and other metals), in turn leading to the adoption of new materials, and advancement or novel use of old ones.
At the same time, there was a rapid demand for structures during the war (such as military and governmental facilities) as well as for housing after the war. These factors would accelerate experiments with prefabricated building.
Quonset hut en route to Japan

16. International Style Quonset hut en route to Japan
World War II (1939–1945) and its aftermath was a major factor in driving innovation in building technology, and in turn, architectural possibilities.
The wartime industrial demands resulting in a supply shortage (of such things as steel and other metals), in turn leading to the adoption of new materials, and advancement or novel use of old ones.
At the same time, there was a rapid demand for structures during the war (such as military and governmental facilities) as well as for housing after the war. These factors would accelerate experiments with prefabricated building.
Quonset hut en route to Japan