# Encyclopedia of Complexity and Systems Science

Living Edition
| Editors: Robert A. Meyers

# Unconventional Computational Problems

Living reference work entry
DOI: https://doi.org/10.1007/978-3-642-27737-5_680-1

## Glossary

The processor of a computer is that component in charge of executing the operations of an algorithm.

A time unit is the length of time required by a processor to perform a step of its computation, consisting of three elementary operations: a read operation in which it receives a constant number of fixed-size data as input, a calculate operation in which it performs a fixed number of constant-time arithmetic and logical calculations (such as adding two numbers, comparing two numbers, and so on), and a write operation in which it returns a constant number of fixed-size data as output.

A sequential computer, consists of a single processor. A parallel computer has n processors, numbered 1 to n, where n ≥ 2. Both computers use the same type of processor, and that processor is the fastest possible (Akl 1997). The assumption that the computers on hand, whether sequential or parallel, use the fastest conceivable processor is an important one. This is because the speed of the...

## Keywords

Parallel Computer Turing Machine Algorithmic Step Single Processor Finiteness Condition
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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