Polygonum is a genus of flowering plants in the family Polygonaceae, commonly known as the knotweed family. This genus includes a variety of species, many of which are found in temperate regions around the world. They are characterized by their jointed stems and alternate leaves, and some species are known for their climbing or sprawling growth habits. Many Polygonum species are used in traditional medicine and as food sources. For example, Polygonum cuspidatum, also known as Japanese knotweed, is noted for its high levels of resveratrol, a compound believed to have health benefits. Some species can also be invasive, affecting local ecosystems.