Cloud computing is a new paradigm that delivers IT services over the internet. It involves using computing resources that are delivered as services over the network. There are three main types of cloud services: Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). Virtualization allows multiple virtual operating systems to run on a single physical computer, masking server resources from users. The future of cloud computing includes global cloud ecosystems, new business models, and more sustainable data centers.