Cloud computing is a transformative paradigm in information technology that revolutionizes the way computing resources are accessed, provisioned, and managed. Instead of relying on local servers or individual devices, cloud computing leverages a network of remote servers to store, manage, and process data over the internet. This model allows users to access computing resources on-demand, providing scalability and flexibility. Key characteristics of cloud computing include self-service, broad network access, resource pooling, rapid elasticity, and measured service. Service models include Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). Common deployment models are public, private, hybrid, and multi-cloud. Cloud computing has become integral to modern IT infrastructure, enabling businesses and individuals to efficiently deploy applications, store data, and leverage computing power without the need for significant upfront investments in hardware or infrastructure.