ram

Ram, in the Bible.

1 Ancestor of David. In the New Testament he is called Aram.

2 Son of Jerahmeel.

3 Ancestor of Elihu.

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ram

Projection fixed to the front end of a fighting vessel and designed to damage enemy ships struck by it. It may have been developed by the Egyptians as early as 1200 BC, but it was most commonly used on Phoenician, Greek, and Roman galleys. It was briefly revived in the mid-19th century, notably in the American Civil War, when rams mounted on armored, steam-driven warships were used effectively against wooden sailing ships. Improvements in naval weaponry and the spread of metal-hulled ships soon made it obsolete again. See also battering ram.

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RAM

 in full random-access memory

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.

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(Random Access Memory) A type of memory chip that is "byte addressable" and provides direct access to any location on the chip. The contents of any byte can be read or written without regard to the bytes before or after it. The most common RAM chip is the dynamic RAM (DRAM) used as the computer's main memory. Any chip that has RAM in its name implies this byte addressing flexibility, such as SRAM, SDRAM, PRAM, MRAM, NVRAM, NRAM and FeRAM. See memory types, memory module, dynamic RAM and static RAM. To learn more about how memory works, see computer and memory.

Some Old Fashioned RAM

Not exactly random access, and hardly a chip, this magnetic drum unit was the memory in the IBM 650 computer, introduced in 1954. It held two thousand 10-digit words. That much memory today would fit inside the period at the end of this sentence. See also core storage and early memories. (Image courtesy of the Hagley Museum and Library.)

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RAM - Random Access Memory