Pisum sativum, the common pea (also known as the garden or field pea), is an herbaceous annual in the Fabaceae (formerly Leguminosae) family, originally from the Mediterraean basin and Near East, but now widely grown for its seedpod or legume (a simple dry fruit containing several seeds and splitting along seams on two sides). The term “pea” can refer to small spherical seed or to the pod. The name “peas” is also used to describe other edible seeds from the Fabaceae, such as chickpeas (Cicer arietinum), pigeon peas (Cajanus cajan), cowpeas (Vigna unguiculata), and sweet peas (several Lathyrus spp.), which are grown as ornamentals.

P. sativum cultivars are either low growing (less than 0.75 meters) or vining. The vining cultivars grow thin tendrils from leaves that coil around any available support and can climb to be 1–2 m high. P. sativum is a cool-season crop grown in many parts of the world; planting can take place from winter to early summer depending on location. The distinctive flower has 5 fused sepals, 5 petals, 10 stamens (9 fused in a staminal tube and 1 stamen is free), and one carpel, which develops into a pod with multiple peas. The average pea weighs 0.1 to 0.4 grams.

Peas appear to have been cultivated for nearly 7,000 years. The earliest archaeological finds of peas come from Neolithic Syria, Turkey and Jordan. In Egypt, evidence of peas dates from ca. 4800–4400 BC.

Peapods are botanically a fruit, but peas are called a vegetable in cooking. They are used as a vegetable, fresh, frozen or canned, and some varieties, such as split peas, are dried; these varieties are typically called field peas. Along with broad beans and lentils, these formed an important part of the diet of most people in the Middle East, North Africa and Europe during the Middle Ages. By the 17th and 18th centuries it had become popular to eat peas "green," or fresh, while they are immature and right after they are picked, especially in France and England. The popularity of green peas spread to North America, where Thomas Jefferson grew more than 30 cultivars of peas on his estate. The “pease porridge” of nursery-rhyme fame is a traditional dish in England made from yellow dried peas.

Peas are high in fiber, protein, vitamins (folate and vitamin C), minerals (iron, magnesium, phosphorus and zinc), and lutein (a yellow carotenoid pigment that benefits vision). Dry weight is about one-quarter protein and one-quarter carbohydrates (mostly sugars).

Global production in 2009 of green peas was 16 million tons, harvested from 2.1 million hectares, with an additional 10.5 million tons of dried peas, from 6.2 million hectares (FAOSTAT 2011). In some agricultural regions, such as the Punjab in India, peas are second only to wheat as a cultivated crop (Singla et al. 2006).