Late in 1990, Hitachi surprised the world with the first 8-megabyte dynamic random access memory (DRAM) on a single chip. The chip is 10 millimeters by 20 millimeters--the size of a fingernail--and it contains 140 million electronic components, each over 100 times smaller than the diameter of a human hair. Dynamic means that the chip loses its memory unless it is continually powered. Random access means that any part of the memory can be fetched or written to in the same time as any other part. With an access time of 50 nanoseconds (billionths of a second) the chip can output its entire memory, roughly 16 novels' worth of data, in roughly 3.2 seconds. An eyeblink is about 1/10th of a second.
Memory cards are credit card sized random access memories that hold their data without external power. They are low power and they will make disc drives obsolete within 7 years. At present they are expensive, but the price is expected to drop rapidly as technology improves and demand drives their development . Fujitsu, the second largest computer company in the world, and Intel are now working on a 64-megabyte memory card.