Low technologies (or low-tech) are simple technical solutions that address basic needs (water, food production and conservation, energy, housing, transport, etc.) in an autonomous and resilient way. They must be accessible (in terms of the budget and know-how necessary for their manufacture); environmentally friendly (materials, renewable or reclaimed, low-energy, etc.); and use local resources (they are gradually adapted and adapted according to the constraints of different territories and the materials available there).