The memory of a generalized mobile phone system can be divided into "mobile phone running memory" and "mobile phone non-running memory". The "running memory" of a mobile phone is equivalent to the memory (or memory bank) of a computer; The "non-running memory" of a mobile phone, that is, the ROM and hard disk of the mobile phone, is the internal memory of the fuselage (referred to as fuselage memory), which is equivalent to the hard disk of a computer. The larger the "running memory" of the mobile phone is, the mobile phone can run multiple programs smoothly; The larger the "non-running memory" of a mobile phone, just like the larger the hard disk, it can store more data.