Introduction of malevolent circuits is generally referred to as Hardware Trojans in the case of very large-scale integration (VLSI) circuits. In recent years, Hardware Trojans are becoming a major challenge for the different embedded systems, particularly for those used in important and precise applications like healthcare, aeronautics, and military. Trojans that have been proposed so far in the literature have a variety of effects on a device’s reliability and functionality, hence the performance. The device may result into complete malfunctioning, and important information may alter, along wrong outcomes. Thus, assurance of the absence of hardware Trojan in a system is a crucial task in safeguarding its general functionality. Therefore, in this research, we examine and explain the number of methods for identifying malicious circuit alteration made at various stages of the design process. Moreover, the benefits and drawbacks of the recent Hardware Trojan protection methods are examined in further detail. The development tendencies in hardware security are finally emphasized.