Outside the rigorous context of science, prediction is often confused with informed guess or opinion.

A prediction of this kind might be valid and useful if the predictor is a knowledgeable person in the field and is employing sound reasoning and accurate data. Large corporations invest heavily in this kind of activity to help focus attention on possible events, risks and business opportunities, using futurists. Such work brings together all available past and current data, as a basis on which to develop reasonable expectations about the future.

In politics it is common to attempt to predict the outcome of elections through the use of opinion polls. Prediction games have been used by many corporations and governments to learn about the most likely outcome of future events with amazing accuracy.

Predictions have often been made, from antiquity until the present, by resorting to paranormal or supernatural means, such as prophecy or by observing omens. Disciplines including water divining, astrology, numerology, and fortune telling, along with many other forms of divination, have been used for centuries or even millennia to predict or attempt to predict the future. So far none of these means of prediction have been proven under controlled conditions and are heavily criticised by scientists and skeptics.