This review provides basic information on spintronics. Briefly described the effects on which the development of spintronic nanoscale devices are based: giant magneto-resistance, spin-dependent tunnelling effect, transport of spin-polarized current, the creation of spin polarized current torque for a magnetic switch and the motion of the magnetization of magnetic domains. As a example of successive applications spin-dependent devices are given parameters of magnetic memories based on use of spintronics components. It is shown that such memory is competitive to nowadays standard memories (at 90 nm) and has the po tential for future development (for example, re ducing the critical size to 32 nm).