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garbage in, garbage out

This saying points out the fact that a computer can do only what it is programmed to do and is only as good as the data it receives and the instructions it is given. If there is a logical error in software, or if incorrect data are entered, the result will probably be either a wrong answer or a system crash.

Note

The saying is sometimes shortened to “GIGO” (GUY-go).
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.