The abstract below provides an overview of the chapter and explains how quantum computing would impact security and cryptography. This highlights the threats of quantum algorithms against existing systems such as RSA and ECC while also presenting the introduction for designing PQC protocols. It discusses about new cryptographic approaches which include lattice-based, code-based and hash based schemes along with quantum key distribution (QKD) for secure communication. Furthermore, it covers attempts to standardize post-quantum algorithms and the challenges with transitioning from undergoing research towards practical quantum-secure systems. Due to the ever-changing quantum technologies, a solution that could equally address classical data protection with future needs would be based on a hybrid model combining both types of approaches.