Magnetoresistive Random Access Memory (MRAM) is a non-volatile memory technology that has been developed since the 1990s. Unlike conventional RAM chip technology, data in MRAM is not stored as a charge or current but is stored by a magnetic storage element. The basic features for MRAM are non-volatile, high capacity density, and long life. In this talk, I will first introduce the concept of “storage” and “memory” in electronic devices, and then show the development history of RAM, especially for the MRAM. At last, I will make a discussion about what can the theoretical or computational physicists do for MRAM.