Human beings have been using plants and animals for food, shelter, clothing, medicines, etc. ever since he arrived on the earth. In tropical countries, people living in villages, biodiversity rich areas and forests have been using indigenous plants as medicines since ages. This traditional knowledge developed over centuries of experience, close observation of nature, trial of natural resources, inference and inheritance. The potential of human beings to utilize the natural resources for their welfare made them the most successful creatures on planet earth. Sustenace of human life on earth requires understanding the role of plants in past and current day cultures.