SSD(SOLID
STATE DRIVES)
A solid-state drive (SSD) (sometimes referred to as
a "solid-state disk" or "electronic disk") is a data
storage device that uses integrated circuit assemblies as memory to store data
persistently. SSD technology uses electronic interfaces compatible with
traditional block input/output (I/O) hard disk drives. SSDs do not employ any
moving mechanical components, which distinguishes them from traditional
magnetic disks such as hard disk drives (HDDs) or floppy disks, which are
electromechanical devices containing spinning disks and movable read/write
heads. Compared with electromechanical disks, SSDs are typically less
susceptible to physical shock, are usually silent, and have lower access time
and latency. However, while the price of SSDs has continued to decline in 2012,
SSDs are still about 20 times more expensive per unit of storage when compared
to HDDs.
PCI-E, DRAM, and NAND based SSD
SSDs share the I/O interface technology developed
for hard disk drives, thus permitting simple replacement for most applications.
As of 2010, most SSDs use NAND-based flash memory,
which retains data without power. For applications requiring fast access, but
not necessarily data persistence after power loss, SSDs may be constructed from
random-access memory (RAM). Such devices may employ separate power sources,
such
