Garbage In Garbage Out (GIGO) is popular computing slang for “if you input the wrong data, the results will also be wrong.” The term arose in the programming community, where instructors remind students that they must check and re-check their data and coding to ensure that the results are valid. The term is also widely used in other industries, most notably in the recording industry, where people stress the need for good equipment. In this case, a poor initial recording will result in an album of low quality.
George Fuechsel, an early IBM programmer, is generally credited with coining the term. He reminded students that computers will process any kind of information they are given without judgment or an eye for accuracy. If mistake is made in the program, however small, it can result in Garbage In Garbage Out, and thereby create an unintended result. As long as people are aware of the fallibility of computers, this concept isn't a big issue, although it can be frustrating on a major project. It does, however, become a problem when people accept information on faith simply because it came from a computer.
When this happens, it is sometimes jokingly called Garbage In Gospel Out. Many computer users are guilty of assuming that computers are infallible and will always return correct results. This can cause serious problems. On a minor level, someone could simply have incorrect facts about a situation; on a major level, someone could base a serious decision on erroneous information.
Programmers try to be aware of the GIGO principle, and in fact many computers have the capacity to check code for basic errors. Most input data, however, still needs to be proofread, especially if it is complex and filled with multiple arguments, which usually is the case with advanced computing. This is one reason scientists like to confirm data with other scientists — to ensure that their calculations are correct.
The principle of Garbage In Garbage Out can apply to many things in life. Cooking with poor quality ingredients, often results in a disappointing meal. Likewise and on a more serious level, students who suffer from a poor education often struggle to succeed in life. The lesson is to ensure that something is of good quality before you use it, whether it's code or a new central heating system.