A nomad (Greek: νομάς, nomas, plural νομάδες, nomades; meaning one roaming about for pasture, pastoral tribe) is a member of a community of people who live in different locations, moving from one place to another. Among the various ways Nomads relate to their environment, one can distinguish the hunter-gatherer, the pastoral nomad owning livestock, or the "modern" peripatetic nomad. As of 1995, there were an estimated 30–40 million nomads in the world.
Nomadic hunting and gathering, following seasonally available wild plants and game, is by far the oldest human subsistence method. Pastoralists raise herds, driving them, and/or moving with them, in patterns that normally avoid depleting pastures beyond their ability to recover.
Nomadism is also a lifestyle adapted to infertile regions such as steppe, tundra, or ice and sand, where mobility is the most efficient strategy for exploiting scarce resources. For example, many groups in the tundra are reindeer herders and are semi-nomadic following forage for their animals. These nomads sometimes adapt the use of high technology such as solar photovoltaics to reduce their dependence on diesel fuel.
Sometimes also described as "nomadic" are the various itinerant populations who move about in densely populated areas living not on natural resources, but by offering services (craft or trade) to the resident population. These groups are known as "peripatetic nomads".