Time series methods or models makes reference to models use in forecasting where no "explanatory" variables are involved. Hence, the only source of information is the past values of the variable of interest.
The main objective of these methods is forecasting future values. These models include smoothing methods (moving averages, single and double exponential smoothing, Holt-Winters exponential smoothing), ARIMA (AutoRegressive Integrated Moving Average) models, and other models.