This science is complete in itself.
Happiness to the whole world it can bring
All the four benefits it bestows on you
Rightful living, money, fulfillment of desires and bliss
Are all available in this world itself
~ Viswakarma in Vaastushastra

Vaastu Shastra is the ancient Indian science of architecture, which governs town planning and designing of man-made structures. A part of the Vedas, the word 'Vaastu' in Sanskrit means 'dwelling', and in the modern context it covers all buildings. Vaastu pertains to the physical, psychological and spiritual order of the built environment, in consonance with the cosmic energies. It is a study of planetary influences on buildings and the people who live in them, and aims at providing guidelines for proper construction.
Hindus believe that for peace, happiness, health and wealth one should abide by the guidelines of Vaastu while building a dwelling. It tells us how to avoid diseases, depression and disasters by living in structures, which allow the presence of a positive cosmic field. Since Vedic wisdom is considered to be synonymous with divine knowledge of the cosmic mind obtained by sages in deep states of meditation, Vaastu Shastra or the science of Vaastu is thought to contain the guidelines given by the Supreme Being. Delving into history, we find that Vaastu developed during the period of 6000 BC and 3000 BC (Ferguson, Havell and Cunningham) and was handed over by ancient architects through word of mouth or hand-written monographs.
The principles of Vaastu had been explained in ancient Hindu scriptures like Skanda Purana, Agni Purana, Garuda Purana, Vishnu Purana, Bruhatsamhita, Kasyapa Shilpa, Agama Sastra and Viswakarma Vaastushastra.
The fundamental premise of Vaastu rests on the assumption that the earth is a living organism, out of which other living creatures and organic forms emerge, and so every particle on earth and space possesses 'live energy'. According to Vaastushastra five elements - Earth, Fire, Water, Air or atmosphere and Sky or space - govern the principles of creation. These forces act for or against each other to create harmony and disharmony. It also says that everything on earth - in some form or other - is influenced by the nine planets, and each of these planets guards a direction. So our dwellings are under the influence of the five elements and the nine planets.