Snow pea is a legume, more specifically a variety of pea eaten whole in its pod while still unripe. Snow peas are also known as mangetout, which is French for "eat it all." The French name comes from the fact that the whole pea - including the pod - is eaten. The name mangetout (French for “eat all”) can apply both to snow peas and to snap peas.
Snow peas, along with sugar snap peas and unlike field and garden peas, are notable for having edible pods that lack inedible fiber (in the form of "parchment", a fibrous layer found in the inner pod rich in lignin) in the pod walls. Snow peas have the thinner walls of the two edible pod variants.
Their sweet flavor also contrasts nicely with seasoned meat or poultry.