Processor register

In computer architecture, a processor register is a small amount of storage available on the CPU whose contents can be accessed more quickly than storage available elsewhere. Most, but not all, modern computer architectures operate on the principle of moving data from main memory into registers, operating on them, then moving the result back into main memory—a so-called  load-store architecture. A common property of computer programs is locality of reference, that is the same values are often accessed repeatedly; and holding these frequently used values in registers improves program execution performance.
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