Botany is the study of plants and includes plant classification, structure, physiology, and economic importance within human society. In the strictest sense, botany is the study of those organisms containing chlorophyll, however for historical reasons, it generally includes the study of non-chlorophyll-containing organisms such as the fungi.

Historically, the formal study of botany can be traced to the ancient Greeks and Romans. For them, botany was merely a part of the study of nature and natural history, rather than a distinct subject in its own right. Botany as a formal and separate subject did not exist until the mid-seventeenth century. The word botany comes from the Greek word botane, meaning plant or pasture.

At its inception, botany consisted of a purely comparative physical system in which plants were grouped together by appearance. Early in botany's history, the doctrine of signatures was used to classify plants. This stated that...