Magnetoresistive Random-Access Memory (MRAM) is a non-volatile random-access memory technology. Data in MRAM is stored by magnetic storage elements. The elements are formed from two ferromagnetic plates, each of which can hold a magnetization, separated by a thin insulating layer. One of the two plates is a permanent magnet set to a particular polarity; the other plate's magnetization can be changed to match an external field to store memory. The simplest method of reading is accomplished by measuring the electrical resistance of the cell.
MRAM time access (speed) is density dependent; between 200 ns and 2μs. Its write time is 100-200 nsec. Endurance, in MRAM, does not know any limitation.  MRAM cost is today potentially moderate. Researches are focused on read speed limitations.

fig1 : Simplified structure of an MRAM cell