Binary recycled pulsars: a powerful physical laboratory

We discuss the problems of formation and evolution of pulsars in close binaries. The first discovered binary pulsar called Hulse-Taylor pulsar, on the name of discoverers. Observations indicate to existence of single recycled pulsars, and disruption of pulsar pairs. by the mechanism of enhanced evaporation is considered. The best laboratory of a study of General Relativity is a system of two neutron stars, where one, or two of them are radiopulsars. Hulse-Taylor pulsar, and recently discovered system containing two radiopulsars (a Double pulsar system) are the best objects for these studies. In addition to checking the validity of general relativity, these systems are used for putting limits to the variability of the gravitational constant. At the end the ”Space Watch” device is described, which may permit to obtain the most precise universal time for the people on Earth.