Bamboo is a group of perennialevergreens in the true grass family Poaceae, subfamily Bambusoideae, tribe Bambuseae. Giant bamboos are the largest members of the grass family. In bamboo, the internodal regions of the stem are hollow and the vascular bundles in the cross section are scattered throughout the stem instead of in a cylindrical arrangement. The dicotyledonouswoodyxylem is also absent. The absence of secondary growth wood causes the stems of monocots, even of palms and large bamboos, to be columnar rather than tapering.
Bamboos are some of the fastest growing plants in the world, as some species have been recorded as growing up to 100 cm (39 in) within a 24 hour period due to a unique rhizome-dependent system. Bamboos are of notable economic and cultural significance in South Asia, South East Asia and East Asia, being used for building materials, as a food source, and as a versatile raw product.