Vasthu Shastra (vāstu śāstra, also known as Vastu Veda means "science of construction and architecture") is a traditional Hindu system for architecture or constructions by design based on directional alignments. It is primarily applied in Hindu architectural constructions, especially for Hindu temples and palaces. It is a part of Yajurveda (written in 4000 B.C). It is believed to be told by the great Viswakarma, the architect for Gods.
Vastu sastra, is basically tells how to contruct a building to utilize the full benefits of five basic elements (known as Panch Maha Bootha) which makes the world running. The Five elements are Bhoomi (Earth), Jala (Water), Vayu (Air), Agni (Fire) and Akhasa (Space). Any house which built as per vasthu shastra will have full ventilation (Fresh Air, suffcient light, clean surrounding) which means healthier & wealthy life. The building which is being constructed as per vasthu will use the natural light (sunlight) to the maximum extent possible and also enough circulation of air. The vasthu shastra describes differently to each building facing different directions, considering Vasthu Purusha Mandala (8 corners or direction like east, northeast etc) of the building (like West facing, north facing.)
Vasthu being designed only for India after considering the Sun, Moon & Planets, habits and notably the monsoon period.(A monsoon is traditionally defined as a seasonal reversing wind accompanied by seasonal changes in precipitation). Hence, Vasthu at present, applicable only to India. If anyone wish to consider Vasthu for other countries, they need to study indepth, understand, and make the neccessary changes needed after considering their monsoon period, habits of the people etc. Hence Vasthu can be considered as a science in India whereas it can be studied only as an art in other countries till they make necessary changes with respect to their place (country). (Otheriwse the people of other countries can pray for Mr.Viswakarma to born again or send his representative to formulate exclusive Vasthu Shastra for them).
Let us see each and every thing in Vasthu (like, Panch Maha booth, Vasthu Purusha Mandala, Prana, 9 vasthu remedial days, Vasthu for House, Vasthu for shop etc.)