Since time immemorial, people have applied their own names, which we now refer to as common, local or vernacular names, to the plants around them. These names are often based on some feature of the plant that has little or no bearing on its relationship to other species in a genetic hierarchy. We issue a word of caution here, since one common name will often refer to a number of species in the same genus or family, or may simply refer to plants with the same leaf shape or flower colour. It may also simply be related to some aspect of the plant's application, or its place or environment of origin. These names can also vary markedly between and within region and language. The Linnaean binomial nomenclature system was developed to provide a universal system of plant classification. To avoid confusion, it is always best to use this system to refer to a particular plant i.e. Genus species authority e.g. Acroceras macrum Stapf.