The testing of a financial model by using it on past date and then comparing the 'predictions' to what actually happened.... more on: Back-testing

The testing of a strategy based on historical data to see if the results are consistent.

A strategy is tested or optimized on historical data and then is applied to new data to see if the results are consistent.

The process of testing a trading strategy (primary technical) through use of historical data.

The process of testing a set of rules that constitutes a mechanical trading system on historical data to determine the viability of the method. This normally involves optimization of the parameters for the trading rules employed and should also include Walk Forward testing to ensure the optimized parameters are stable.