Methods of determination of the energy and mass of primary cosmic ray particles at extensive air shower energies

Measurements of cosmic ray particles at energies above E greater than or similar to 5 x 10(14) eV are performed by large-area ground-based air shower experiments. Only they provide the collection power required to obtain sufficient statistics at the low flux levels involved. In this review we, briefly outline the physics and astrophysics interest of such measurements and discuss in more detail various experimental techniques applied for reconstructing the energy and mass of the primary particles. These include surface arrays of particle detectors as well as observations of Cherenkov and of fluorescence light. A large variety of air shower observables is then reconstructed from such data and used to infer the properties of the primary particles via comparisons to air shower simulations. Advantages, limitations and systematic uncertainties of different approaches will be critically discussed.