This document presents a study on secure multi-authentication data classification models in cloud computing environments, focusing on the application of improved Bayesian techniques for data classification and encryption of sensitive data. It discusses cloud computing's architecture, deployment models (public, private, hybrid, and community), and the significance of data classification using machine learning algorithms to enhance security and optimize data management. The authors explore various security issues, risks, and proposed solutions pertinent to cloud environments, drawing on multiple literature sources while identifying gaps for future research.