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Tick ( ) if you know this.
                       ▶   Data and information on a computer is stored in the form of 0s and 1s, called binary digits.

                       ▶  1 Terabyte is equal to 1024 Gigabytes.



                  SECONDARY MEMORY

                  Secondary memory  is the external memory of the computer that can store large
                  amounts of data permanently. It is not directly accessed by the CPU. It is cheaper in
                  comparison to primary memory. Secondary memory devices are also called secondary

                  storage devices.

                  Hard Disk

                  Hard disk is the main secondary storage device, used to store data
                  and information. It is fixed inside the CPU cabinet. It consists of one or
                  more  magnetic  disks  which is  used  to  store  and restore  digital

                  information for usage.                                                                Hard Disk

                                Compact Disc (CD)

                                CDs are circular in shape. It can store a large amount of data and can be
                                carried from one place to another easily. It can store up to 700MB of data.

                      CD        There are three types of CDs:
                     Compact Disc-Read Only Memory (CD-ROM): It contains data that has been written
                    at the time of manufacturing and cannot be modified or erased.

                     Compact Disc-Recordable (CD-R): It allows only one-time recording. Data written once
                    cannot be erased.
                     Compact Disc-Rewritable (CD-RW): It allows multi-reading. Data written on it can be

                    erased or rewritten.

                  Digital Versatile Disc (DVD)
                  A DVD looks like a CD and can store up to six times more data than a CD.

                  There are two types of DVDs:
                                                                                                               DVD
                                                                                         21 st
                     Digital Versatile Disc-Recordable                                Century   #Initiative
                                                                                        Skills
                    (DVD-R): It allows only one-time
                    recording.                                   “Do not hesitate to clear doubts from your
                                                                 teachers. Learn something new every day.”
                     Digital  Versatile Disc-Rewritable
                    (DVD-RW): It allows to delete and
                    rewrite data on it.



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