Platform as a Service (PaaS) provides a cloud-based solution for renting hardware, software, and network resources, enabling users to develop, run, and manage applications without the complexity of maintaining the underlying infrastructure. PaaS reduces administrative effort, improves scalability, and lowers costs while providing a range of services, including database management and support for various programming languages. Key providers like Google, Microsoft, and Heroku offer flexible platforms that facilitate rapid application development and deployment.