Simple exponential smoothing is a forecasting technique used to predict future values based on past observations. It assigns exponentially decreasing weights to older data, meaning more recent observations have a greater influence on the forecast. This method is particularly useful for time series data without trends or seasonal patterns. The formula for simple exponential smoothing involves a smoothing constant, often denoted as alpha, which ranges between 0 and 1. A higher alpha gives more weight to recent data, while a lower alpha smooths the forecast more. This approach is straightforward and effective for short-term forecasting.