Cloud computing offers cost efficiency and scalability but introduces significant security concerns related to data control. Cryptography addresses these concerns by ensuring data confidentiality, integrity, authenticity, and availability . This research document provides an in-depth analysis of cryptographic techniques in cloud computing, including symmetric and asymmetric encryption, homomorphic encryption, and post-quantum cryptography. It critically evaluates the strengths and limitations of current approaches, particularly in key management and data-in-use protection, and explores future directions and a proof of concept to enhance cloud security.