TYPES OF MAIN MEMORY

--->There are two types of main memory
       1)RAM[RANDOM ACCESS MEMORY]
       2)ROM[READ ONLY MEMORY]

1)RAM OPERATION:

--->RAM is a volatile memory.
--->All data  in RAM is lost,when computer is switched off.
--->two types of RAM
      1)Static RAM
      2)Dynamic RAM
--->READ AND WRITE opearion is performed
--->Non volatile RAM also designed and used nowadays ex;RRAM(RESISTIVE RANDOM           ACCESS MEMORY)

2)ROM OPERATION:
--->Data is permanently  stored even when the computer  is switched off.
--->It stores the program in the manner of bootstrap loader.
--->Access time of between 10&50nanoseconds
--->READ operation only performed.

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