Calorimeters are used to measure the energy of particles including electrons. The CDF detector at Fermilab has an electromagnetic calorimeter designed to measure the interactions (showers) of caused by electrons or photons (and to a much lesser extent other particles). Behind the electromagnetic calorimeter is the hardronic calorimeter. The other large experiment at the Fermi lab's Tevatron (D0) has a similar configuration with a different design. The two large multi purpose detectors at CERN (Atlas and CMS) are constructed the same way. As was pointed out the readout of the calorimeter is digitized (the way we get the information out of the Calorimeters is digitized), though the detectors themselves are not digital devices.