In this paper, we analyze ferroelectric (FE) and anti-ferroelectric (AFE) field effect transistors (FETs) (shown in Fig. 1(a)) and compare their subthreshold characteristics and hysteretic behavior. To facilitate this analysis, we develop a Preisach based  circuit compatible model for FE/AFE. Whereas in FE capacitor the two stable polarization (P) states are -PR and +PR, in case of AFE capacitor, non-volatility can be achieved within →+PR by imposing a built-in potential through work-function engineering (Fig, 1(b)). However, in FE/APEFETs, FE/AFE can be partially polarized (forming minor P-Vloop), which we analyze in this paper. Finally, correlating the negative capacitance (NC) effect in FE/AFE with domain-wall propagation , we explore the steep subthreshold swing (SS) characteristics of FE/APE-FET and analyze their transient nature and dependence on flat-band voltage (VFB) and maximum applied gate voltage (VGS).