Magnetic disks are the predominant storage media in personal computers. Optical discs, however, are almost exclusively used in the large-scale distribution of retail software, music and movies because of the cost and manufacturing efficiency of the molding process used to produce DVD and compact discs and the nearly-universal presence of reader drives in personal computers and consumer appliances.[1] Flash memory (in particular, NAND flash) has an established and growing niche as a replacement for magnetic hard disks in high performance enterprise computing installations due to its robustness stemming from its lack of moving parts, and its inherently much lower latency when compared to conventional magnetic hard drive solutions. Flash memory has also long been popular as removable storage such as USB sticks, where it de facto makes up the market. This is because it scales better cost-wise in lower capacity ranges, as well as its durability. It has also made its way onto laptops in the form of SSDs, sharing similar reasons with enterprise computing: Namely, markedly high degrees of resistance to physical impact, which is again, due to the lack of moving parts, as well as a performance increase over conventional magnetic hard disks and markedly reduced weight and power consumption. Flash has also made its way onto cell phones.[2][3]
The design of computer architectures and operating systems are often dictated by the mass storage and bus technology of their time.[4]