The text discusses time series analysis, a method used by commercial, scientific, and other organizations to better predict data trends over different time periods. It highlights the difference between stationary and non-stationary data trends, with stationary data having constant variance over time and non-stationary data showing seasonal fluctuations. The Dicky-Fuller test is used to determine if a given data model is stationary or non-stationary, and its results can help verify if the time series follows a stationary pattern or has a non-stationary pattern. First-order and second-order time series differencing are also discussed as methods to convert non-stationary time series into stationary ones, with logarithmic transformation being one of the approaches used.