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Read-Only Memory (ROM):  ROM is a permanent memory that holds
                                        essential instructions for starting the computer. It keeps data even when
                                        the computer is off, making it non-volatile. This memory helps the system
                                        boot up and run properly.


                  Difference between RAM and ROM
                  The difference between RAM and ROM is given in the table below:

                   Feature           RAM (Random Access Memory)                ROM (Read-Only Memory)
                   Nature            Temporary memory (volatile)               Permanent memory (non-volatile)
                   Data Retention Loses data when power is turned off          Retains data even when power is off

                   Purpose           Stores data and instructions for active  Stores essential instructions for
                                     processing                                booting the computer
                   Speed             Fast access speeds                        Slower access speeds

                   Usage             Enables multitasking and efficient        Contains firmware and critical
                                     processing                                system-level instructions

                      Secondary Storage Devices: Secondary storage is memory that keeps data even when the
                     computer is off. Unlike primary memory, it’s accessed through the operating system and used
                     for long-term storage. It is cheaper than primary memory and examples include CD, DVD,
                     and SSD.

                            Hard Disk: A hard disk consists of magnetic disks called platters, where
                         data is stored using a magnetic head in circular tracks. It offers long-
                         term data storage with capacities ranging from gigabytes to terabytes.
                         The hard disk is fixed inside the computer, allowing faster data access
                         compared to CDs. External hard disks can be connected via USB for extra storage.
                                                      Solid State Drive (SSD): An SSD is a storage device that keeps
                                                 your files, like photos and games. It uses flash memory, making it
                                                 faster and more reliable than a hard disk. SSDs are durable and
                     come in sizes  from 128 GB to several TB. Many modern computers use SSDs  instead of
                     traditional hard drives.

                            CD: A CD is a small, round disc used to store music, videos, and data in
                         digital form, holding up to 700 MB. Originally made for sound recordings,
                         it later  stored  other  types  of information.  Nowadays,  CDs are  mostly
                         outdated, replaced by better storage options
                                       Digital Versatile Disc (DVD): DVDs are used for storing digital data using
                                    optical rays. It is the same size as a CD but has a larger storage capacity. They
                                    are commonly used to store large volumes of data, including audio and video
                                    files. It stores data up to 10 GB.

                            Blu-ray Disc: A Blu-ray disc is an optical disc that stores large amounts of
                         data and plays videos. It can hold up to 25 GB of data, much more than
                         a DVD, which holds about 4.7 GB. The key difference is Blu-ray’s larger
                         storage capacity.


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