there are two type of memory (1) is primary
(2)is secondary
Primary is divided in two part
(1) ROM
(2)RAM
ROM- IT is divided in three part prom, eprom, eeprom
RAM- RAM IS DIVIDED IN TWO PART SRAM DRAM
SRAM - IT divided in cache ram
DRAM- ITdivided in four part edo dram , sdram, ddrram, rdram , sgram, fpm dram, vram
Now SECONDARY MEMORY-ALL the storage device like floppy, hdd,dat, zip. Come into secondary memory.