Aristotle was a Greek philosopher born in 384 BC who made the first scientific attempt to classify living organisms. In his book "History of Animals", he developed the first system of classification, grouping organisms into plants and animals. Plants were further classified as herbs, shrubs, or trees based on their size and morphology. Animals were classified based on whether they had blood or not, or based on their habitat or movement. This two-group system formed the basis of taxonomy, the scientific study of naming and grouping organisms.