A solid-state drive (SSD, also known as a solid-state disk[1][2][3]) is a solid-state storage device that uses integrated circuit assemblies as memory to store data persistently. SSD technology primarily uses electronic interfaces compatible with traditional block input/output (I/O) hard disk drives (HDDs), which permit simple replacements in common applications.[4] New I/O interfaces like SATA Express and M.2 have been designed to address specific requirements of the SSD technology.