This chapter is devoted to the recently proposed both discrete variable (DV) and continuous variable (CV)-QKD schemes. The chapter starts with the description of Hong-Ou-Mendel effect and photonic Bell state measurements (BSMs). Both polarization states-based and time-bin-states-based BSMs are introduced. After that the BB84 and decoy-state protocols are briefly revisited. The next topic in the chapter is devoted to the measurement-device-independent (MDI)-QKD protocols. Both polarization states-based and time-phase states-based MDI-QKD protocols are described. Further, the twin-field (TF)-QKD protocols are described, capable of beating the Pirandola-Laurenza-Ottaviani-Banchi (PLOB) bound on a linear key rate. Floodlight (FL) CV-QKDContinuous variable (CV)-QKD protocol is then described, capable of achieving record secret-key rates (SKRs). Further, the Kramers-Kronig (KK)-receiver-based CV-QKD scheme is introduced, representing high-SKR scheme of low-complexity. Finally, the entanglement based CV-QKD scheme with information reconciliation over the entanglement assisted link is described.