Buds are small swellings or bumps on the stem around the node. They contain meristem tissue that when differentiated will become a particular plant organ such as a stem, leaf, or flower. Three types of buds exist, those that produce stems, others that produce leaves, and still others that produce flowers. They are therefore called leaf buds, flower buds, and stem buds. The stem buds are named for where they exist on the stem, apical or terminal if they exist at the top or end of the stem and lateral if they exist at the nodes below the terminal or apical bud. One other type of bud exists, known as adventitious buds. These buds arise at any place along the stem, generally in response to injury of the stem. It is a survival mechanism for the plant.
An undeveloped stem, consisting of a tiny bundle of cells, from which leaves, lateral buds, flower parts or all three will arise.