A system for categorizing plants by their species and genera, and allocating these into higher groups. There are many taxonomic systems but modern classifications group species according to their genetic relationships, such that each group is monophyletic. The most widely used classification places all living organisms within three domains: Bacteria, Archaea, and Eukarya, and each domain is divided into kingdoms. In 1998 a group of plant taxonomists, known as the Angiosperm Phylogeny Group (APG), devised a new classification of the plant kingdom based on phylogeny. Under the APG classification the common daisy (Bellis perennis) is classified as:

• Domain: Eukarya

• Kingdom: Plantae

• Clade: Campanulids

• Order: Asterales

• Family: Asteraceae

• Genus: Bellis

• Species: perennis