Cloud computing allows users to access applications and store data over the Internet instead of locally on personal devices. It provides various services through deployment and service models. The main deployment models are public, private, hybrid, and community clouds. The main service models are Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). IaaS provides fundamental computing resources, PaaS provides platforms for developing and deploying applications, and SaaS provides software applications through the cloud.