Architecture is both the process and the product of planning, designing, and constructing buildings or any other structures. Architectural works, in the material form of buildings, are often perceived as cultural symbols and as works of art. Historical civilizations are often identified with their surviving architectural achievements.
The earliest surviving written work on the subject of architecture is De architectura, by the Roman architect Vitruvius in the early 1st century AD. According to Vitruvius, a good building should satisfy the three principles of firmitas, utilitas, venustas, commonly known by the original translation – firmness, commodity and delight. An equivalent in modern English would be:
Durability – a building should stand up robustly and remain in good condition.
Utility – it should be suitable for the purposes for which it is used.
Beauty – it should be aesthetically pleasing.