Random-access memory

Random-access memory (RAM) is computer memory whose locations can be read or written directly by address, without traversing intervening locations. It is commonly used as a computer’s working memory.

Dynamic random-access memory: A semiconductor memory that stores each bit as charge in a capacitor and periodically refreshes it. Its capacitor cells make it the dominant technology for main memory.
Bit: The smallest unit of digital information, with a value of zero or one. RAM represents stored information as collections of bits.
Main memory: The computer memory directly available to the processor for currently needed programs and data. RAM commonly implements the main memory used during program execution.
Flash memory: Nonvolatile semiconductor memory that stores data in electrically isolated charge-trapping structures. Flash preserves data without power, while typical RAM is faster and volatile.
Static random-access memory: A semiconductor memory that stores each bit in a bistable circuit while power is supplied. Its latch-based cells avoid refresh and provide fast access, at higher cost per bit.
Binary number: A number expressed using the base-two numeral system. Memory addresses and stored values are represented with binary digits.
Virtual memory: A memory-management technique that gives processes address spaces larger than available physical memory. Operating systems use RAM alongside storage to support virtual address spaces.
Hard disk drive: A persistent storage device that records data magnetically on rotating disks. Its mechanical access is slower than RAM, but it stores data without continuous power.
Memory cell: A circuit or physical element that stores one or more bits of information. RAM arrays are built from addressable cells that hold individual bits.
Semiconductor device: An electronic component whose conductivity can be controlled through its material structure or applied signals. Modern RAM cells are implemented using semiconductor devices.

Linked from 29 pages