SSD Solid State Disk Drive

[tentblogger-youtube g321-HoQcSk]

A Solid State Disk Drive (SSD), some times called a solid-state disk drive or electronic disk is a data storage device that uses solid-state memory to store persistent data with the intention of providing access in the same manner as a traditional block i/o hard disk drive. SSDs are different from traditional magnetic disks such as hard disk drives (HDDs) or floppy disk drives which are electro-mechanical devices containing spinning disks and movable read/write heads. In contrast, SSDs use microchips which retain data in non-volatile memory chips and contain no moving parts. Compared to electro-mechanical HDDs, SSDs are typically less susceptible to physical shock, are silent, have lower (i.e. faster) access time and latency but are more expensive per gigabyte (GB). SSDs use the same interface as hard disk drives, thus easily replacing them in some applications that require faster speed and smaller size.

As of 2010, most SSDs use NAND-based flash memory, which retains memory even without power. SSDs using volatile random-access memory (RAM) also exist for situations which require even faster access, but do not necessarily need data persistence after power loss, or use external power or batteries to maintain the data after power is removed.

A hybrid drive combines the features of an HDD and an SSD into one unit, containing a large HDD, with a smaller SSD cache to improve performance of frequently accessed files. These can offer near-SSD performance in most applications (such as system startup and loading applications) at a lower price than an SSD. These are not suitable for data-intensive work, nor do they offer the other advantages of SSDs.