Power Line Communication (PLC) has emerged as a vital technology for enabling data transmission over existing electrical power lines, presenting a cost-effective and efficient solution for the smart grid. This paper explores the potential and challenges of applying PLC within smart grid frameworks, focusing on its role in facilitating two-way communication between grid operators and consumers. By leveraging the already established power distribution network, PLC can support advanced metering infrastructure (AMI), demand response (DR) programs, and other smart grid functionalities without the need for dedicated communication networks. The paper investigates key aspects of PLC systems, including modulation techniques, noise challenges, and signal attenuation factors specific to power line channels. It also examines the two main PLC categories: narrowband and broadband. Narrowband PLC operates at lower frequencies and is suitable for long-distance, low-data-rate applications, whereas broadband PLC offers higher data rates over shorter distances, catering to applications such as video surveillance or real-time data transmission within substations. Additionally, we analyze the integration of PLC with other communication technologies like wireless and fiber optics to address its limitations, thereby ensuring reliable and secure data transmission across varying grid conditions. Security measures in PLC for the smart grid are also discussed, given that PLC channels are susceptible to both eavesdropping and interference, making cybersecurity a critical consideration. In conclusion, this paper demonstrates how PLC can be an integral part of a cost-efficient and scalable communication infrastructure within the smart grid. Although PLC offers promising benefits, certain limitations such as signal degradation and potential noise from electrical equipment necessitate further innovation and hybrid approaches to optimize its performance in real-world smart grid applications.