Skip to main content

Primary memory or Main memory of Computer System || RAM || ROM

In simple words primary memory is the storage device that is directly connected to the CPU and store data temporarily during execution. It implies CPU can directly access primary storage and stores instruction and data for execution or processing. The most popular example of this kind of memory is the RAM that we use in modern day computers. CPU registers, Caches and other memories connected to the CPU local bus falls in this category. Primary storage devices are comparatively faster than all other kinds of memory type. Usually primary storage devices are considered to be directly connected to the processor but in reality modern computers employ components like Virtual memory manager , DRAM controllers etc. In between processor and memory but the notion of direct connection is still valid since these components are transparent to the processor. Volatile memories are used as primary storage.


Main memory is a program where data are kept when the processor is actively using them. When programs and data become active ,they are copied from secondary memory into main memory where the processor can interact with them. A copy remains in secondary memory.

Major Characteristics of Main Memory :

The main memory is central storage unit of a computer system. It is used to store programs and data during the computer operation.

  • The capacity is typically expressed in terms of bytes or words.Common word length 81,632 bits.
  • Main memory is relatively large and fat memory.
  • The unit of transfer is equal to the number of data lines into & out of the memory module.
  • Typically most expensive.
  • Requires the average access time in billionth of a second.

Parts of Main Memory:

Main memory Divided into two parts.

  1. RAM (Random Access Memory)
  2. ROM (Read Only Memory)

Picture of RAM

Picture of ROM

Random Access Memory (RAM)

Ram is a form of data storage that can be accessed randomly at any time, in any order and form any physical location in contrast to other storage devices.. such as hard drives.Where the physical location of the data determines the time taken to retrive it.Ram chips can read data faster than ROM.

To know more in Bangla watch this video

Read Only Memory (ROM)

ROM is a form of data storage in computers and other electronic devices that cannot be easily altered or reprogrammed. RAM is referred to as Volatile memory and lost data when the power is turned off whereas ROM is non-volatile and the contents are retained even after the power is switched off..!

To know more in Bangla overall about memory ,watch this video


Unfamiliar Word Meaning in Bangla

  • Comparatively : অপেক্ষাকৃত,তুলনামূলকভাবে
  • Employ : নিযুক্ত করা,প্রয়োগ করা
  • It implies : এর মানে
  • Notion : ধারণা,বিশ্বাস,খেয়াল,প্রবণতা
  • Transparent : স্বচ্ছ,আলোকভেদ্য
  • Retrive : পুনরূদ্ধার করা
  • Random : এলোমেলোভাবে
  • Retained : অপরিবর্তিত রাখা / ধরিয়া রাখা

*****************************************

Quote:

Stop being a Prisoner of your past ,become the Architect of your Future..