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/ram/, n.computer memory available to the user for creating, loading, or running programs and for the temporary storage and manipulation of data, in which time of access to each item is independent of the storage sequence. Cf. ROM.[r(andom)-a(ccess) m(emory)]
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Computer main memory in which specific contents can be accessed (read or written) directly by the CPU in a very short time regardless of the sequence (and hence location) in which they were recorded.Two types of memory are possible with random-access circuits, static RAM (SRAM) and dynamic RAM (DRAM). A single memory chip is made up of several million memory cells. In a SRAM chip, each memory cell stores a binary digit (1 or 0) for as long as power is supplied. In a DRAM chip, the charge on individual memory cells must be refreshed periodically in order to retain data. Because it has fewer components, DRAM requires less chip area than SRAM; hence a DRAM chip can hold more memory, though its access time is slower.* * *
▪ warship partappurtenance fixed to the front end of a fighting vessel and designed to damage enemy ships when struck by it. It was possibly first developed by the Egyptians as early as 1200 BC, but its importance was most clearly emphasized in Phoenician, Greek, and Roman galleys (seagoing vessels propelled primarily by oars).The ram enjoyed a brief revival in naval warfare in the mid-19th century, notably in the American Civil War and the Austro-Italian War of 1866. At this time rams were mounted on armoured, steam-propelled warships and used effectively against wooden sailing ships. Improvements in naval ordnance and the spread of metal-hulled ships soon made the ram obsolete again, however. See also battering ram.* * *
Universalium. 2010.
