With this presentation, we would like to introduce the meaning of «piezometers», their classification (open and close circuit piezometer), method of reading (deep meter or electrical piezometers), available technologies (piezo resistive or vibrating wire sensor) and the main models available. Electrical piezometers include common vibrating wire piezometers, heavy duty piezometers, multipoint piezometers, removable transducers for Casagrande piezometers, piezo resistive piezometers, titanium piezometers, piezometers for water table level monitoring, drive-in (or push-in) piezometers.