Green beans are the unripe, young fruit and protective pods of various cultivars of the common bean ('Phaseolus vulgaris'). Green beans are known by many common names, including French beans, string beans.

They are distinguished from many other varieties of beans in that green beans are harvested and consumed with their enclosing pods, before the bean seeds inside have fully matured. An analogous practice is the harvest and consumption of unripened pea pods, as is done with snow peas or sugar snap peas.

Historically, green bean pods contained a "string", a hard fibrous strand running the length of one side of the pod. This string was either removed before cooking or made swallowable by cutting the pod into short segments. Modern, commercially grown green bean varieties are "stringless" and lack strings, though heirloom varieties may retain this trait.

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