garbage in, garbage out

Garbage In, Garbage Out (abbreviated to GIGO) is a phrase in the field of computer science. It refers to the fact that computers, unlike humans, will unquestioningly process the most nonsensical of input data and produce nonsensical output. It was most popular in the early days of computing, but has fallen out of use as programs have become more sophisticated and now usually have checks built in to reject improper input. The expression Garbage In, Garbage out was initiated as a teaching mantra by George Fuechsel, IBM 305 RAMAC technician/Instructor, later to evolve into the aphorism GIGO. Programmers were not to complain that a program did not "do the right thing" when given imperfect input. The first example of this was probably cited by Charles Babbage, inventor of the first programmable device who said:

On two occasions I have been asked,—"Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?" [...] I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question.^[1]

It is also commonly used to describe failures in human decision making due to faulty, incomplete, or imprecise data. For example, a poorly typeset TeX document will look bad because the user did not write the TeX source well.

Garbage In, Gospel Out is a more recent expansion of the acronym. It is a sardonic comment on the tendency to put excessive trust in `computerized' data, on the propensity for individuals to blindly accepting what the computer says. Because the data goes through the computer, we tend to believe it.

It can also be used as an explanation for the poor quality of a digitized audio or video file. Although digitizing is the first step in cleaning up a signal, it does not, by itself, improve the quality. Defects in the original analog signal will be faithfully recorded, but may be identified and removed by a subsequent step. (See Digital signal processing.)

"Decision-makers increasingly face computer-generated information and analyses that could be collected and analyzed in no other way. Precisely for that reason, going behind that output is out of the question, even if one has good cause to be suspicious. In short, the computer analysis becomes the gospel." ^[2]

Non-computer-related use of the term

The term can be used in any field in which it is difficult to create a good result when given bad input. For example, in translation, it is difficult to convert a source text that is confused, illogical or missing pertinent information into a quality translation. A translator may use the phrase "Garbage in, garbage out" to explain the importance of good source text to a client. Another example, in quality implications, the quality of the materials a manufacturer procures directly affects the quality of the finished product and, consequently, affects the sale of the finished product. One can explain that if a firm sells a defective product, the product's buyer will become dissatisfied and may refuse to purchase the firm's product in the future. ^[3]

Notes and references

1. ^ Babbage, Charles (1864). Passages from the Life of a Philosopher. Longman and Co., 67. 
2. ^ Daniel T. Brooks, Brandon Becker and Jerry R. Marlatt, "Computer Applications in Particular Industries: Securities" appearing in Bigelow, "Computers & The Law", American Bar Association, Section of Science and Technology, Third Edition 1981 at 250, 253.
3. ^ Management of Business Logistics, 7th ed.

See also

• KIBO
• SNAFU
• FUBAR

This article was originally based on material from the Free On-line Dictionary of Computing, which is licensed under the GFDL.

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