Secondary Storage device Storage capacity 1TB = 1024 GB; 1GB = 1024 MB; 1MB = 1024KB; 1KB = 1024B 210 =1024 1 Byte = 8 bits Access time: It is the average time taken for the device to search and read the required data. Data transfer time: Amount of data can be transferred between main memory and a storage device. Magnetic storage devices Direct Access Floppy disk : 1.44MB Hard disk: Platter / Cylinder / Track Cluster (refer to P.73-75 of textbook) Magnetic tapes (Backup) - sequential access Optical storage device CD-ROM DVD HD DVD Blu-ray Disc Other forms of storage devices Memory cards, USB flash drive SSD hard disk (no rotation needed, higher access time, no defragmentation needed) Network storage 13.6 Latest development of secondary storage device |