ACF (Auto Correlation Function)

PACF (Partial Auto Correlation Function)

AR (Auto Regression)

MA (Moving Average)

ARMA

Invertibility of Time Series

Links

ACF and PACF: https://machinelearningmastery.com/gentle-introduction-autocorrelation-partial-autocorrelation/

ACF and PACF for AR and MA: https://towardsdatascience.com/identifying-ar-and-ma-terms-using-acf-and-pacf-plots-in-time-series-forecasting-ccb9fd073db8