An architectural style is a set of characteristics and features that make a building or structure notable or historically identifiable. It is a sub-class of style in the visual arts generally, and most styles in architecture relate closely to a wider contemporary artistic style. A style may include such elements as form, method of construction, building materials, and regional character. Most architecture can be classified within a chronology of styles which changes over time, reflecting changing fashions, beliefs and religions, or the emergence of new ideas, technology, or materials which make new styles possible.
Styles therefore emerge from the history of a society. They are documented in the subject of architectural history. At any time several styles may be fashionable, and when a style changes it usually does so gradually, as architects learn and adapt to new ideas. The new style is sometimes only a rebellion against an existing style, such as postmodern architecture (meaning "after modernism"), which in 21st century has found its own language and split into a number of styles which have acquired other names.
Architectural styles often spread to other places, so that the style at its source continues to develop in new ways while other countries follow with their own twist. For instance, Renaissance ideas emerged in Italy around 1425 and spread to all of Europe over the next 200 years, with the French, German, English, and Spanish Renaissances showing recognisably the same style, but with unique characteristics. An architectural style may also spread through colonialism, either by foreign colonies learning from their home country, or by settlers moving to a new land. One example is the Spanish missions in California, brought by Spanish priests in the late 18th century and built in a unique style.
After an architectural style has gone out of fashion, revivals and re-interpretations may occur. For instance, classicism has been revived many times and found new life as neoclassicism. Each time it is revived, it is different.
