Modern architecture gained popularity in the second half of the 20th century. It’s
primary characteristic is the simplification of form and creation of ornament from
the structure and theme of the building, eliminating "unnecessary details.” Because
Modern is not a strictly defined style, some believe it evolved technological and
engineering development which allowed builders to use new materials such as iron,
steel, and glass. Other might say that Modern architecture is a reaction against
the eclectic styles of the past.