[en] The NEMO-3 Experiment is planned to test the most troublesome hypothesis of the Standard Model according to which the neutrinos are vanishing-mass fermions carrying a given leptonic quantum number. At low energies this hypothesis can be tested on a very rare nuclear decay mode, the double beta decay. There are several natural even-even isotopes with a lifetime of the order of 10²⁰ years which decay toward a neighbour even-even nucleus by emitting two electrons and two neutrinos with a Q_ββ value of the order of MeV. When the two neutrinos annihilate each other the two electrons carry the available energy, i.e. the end-point of the ββ energy spectrum. Should these two decay modes be experimentally distinguishable, then the 2β decay will check one of the two theories on the nature of neutrino: Majorana neutrinos, i.e. massive particles or Dirac particles, i.e. of vanishing mass as they look like today. More generally, from the β decay we will get information concerning the scattering of two W^- bosons, which could entail extensions of the Standard Model: majoron or other theories. NEMO-3 will be able to lower the upper bound of mass uncertainty to fractions of eV, while the best current estimate is m(ν_e) < 1.3 eV. The NEMO-2 experiment completed in 1996 has provided the following values for the ββ lifetimes measured on ¹⁰⁰Mo and ¹¹⁶Cd, respectively: T_1/2 (2ν) = 0.95 ± 0.10 x 10¹⁹ years; T_1/2 (0ν) = 6.40 x 10²¹ years (95% CL) and T_1/2 (2ν) = 3.75 ± 0.50 x 10¹⁹ years; T_1/2 (0ν) > 5.0 x 10²¹ years (95% CL), respectively. The report gives also information on the construction of NEMO-3 and trigger electronics. The scheme of the logic of decision by the T2 card (second level triggering) and the ensemble scheme of triggering system based on t1-3, t2 cards and TTL Interface are presented