Architectural theory involves the critical thinking, discussion, and writing about architecture, forming a core part of education and practice globally. Its origins date back to antiquity, notably with the Roman architect Vitruvius, whose 1st-century BC treatise De architectura articulated fundamental principles such as "firmness, commodity, and delight." This seminal work, rediscovered in 1414, significantly influenced Renaissance architects by providing a theoretical basis for their designs.

Concurrently, ancient India developed Vastu shastra, a traditional "science of architecture" that guided design principles like spatial geometry and integration with nature, as detailed in texts such as Varahamihira's 6th-century Brihat Samhita. The 20th century witnessed a proliferation of architectural discourse through books and journals, leading to rapid changes in styles and movements. This ongoing dialogue, now further expanded by the internet, continuously shapes how we understand and create buildings.