Forecasting's the process of estimation in unknown situations. Prediction's a similar, but more general term. Both can refer to estimation of time series, cross-sectional or longitudinal data. Usage can differ between areas of application: for example in hydrology, the terms "forecast" and "forecasting" are sometimes reserved for estimates of values at certain specific future times, while the term "prediction"'s used for more general estimates, such as the number of times floods will occur over… (More on Forecast)