literally "science of architecture" are texts on the traditional Indian system of architecture. These texts describe principles of design, layout, measurements, ground preparation, space arrangement, and spatial geometry. The designs aim to integrate architecture with nature, the relative functions of various parts of the structure, and ancient beliefs utilising geometric patterns (yantra), symmetry, and directional alignments. Vastu Shastra are the textual part of Vastu Vidya - the broader knowledge about architecture and design theories from ancient India.Varahamihira's Brihat Samhita dated to about the sixth century CE is among the earliest known Indian texts with dedicated chapters with principles of architecture. For example, Chapter 53 of the Brihat Samhita is titled "On architecture", and there and elsewhere it discusses elements of vastu sastra such as "planning cities and buildings" and "house structures, orientation, storeys, building balconies" along with other topics. Other ancient Vastu shastra works includes Manasara etc. Middle Ages Following the tradition of Vastu shastra, several scholars wrote architectural texts during medieval times which includes Manushyalaya Chandrika, dealing with domestic architecture authored by Thirumangalath Neelakanthan Musath, Samrangana Sutradhara written by Bhoja of Dhar,a poetic treatise on classical Indian architecture etc among others. Throughout the Middle Ages, architectural knowledge was passed by transcription, word of mouth and technically in master builders' lodges. Due to the laborious nature of transcription, few examples of architectural theory were penned during this time. Most written works during this period were theological, and were transcriptions of the Bible. Since the architectural theories were on structures, fewer of them were transcribed. The Abbot Suger's Liber de rebus in administratione sua gestis was an architectural document that emerged with Gothic architecture. Another was Villard de Honnecourt's portfolio of drawings from about the 1230s. In Song Dynasty China, Li Jie published the Yingzao Fashi in 1103, which was an architectural treatise that codified elements of Chinese architecture. Renaissance The first great work of architectural theory of this period belongs to sabona, De re aedificatoria, which placed Vitruvius at the core of the most profound theoretical tradition of the modern ages. From Alberti, good architecture is validated through the Vitruvian triad, which defines its purpose. This triplet conserved all its validity until the 19th century. A major transition into the 17th century and ultimately to the Age of Enlightenment was secured through the advanced mathematical and optical research of the celebrated architect and geometer Girard Desargues, with an emphasis on