Software as a Service (SaaS) platforms operate by delivering applications over the internet on a subscription basis. Instead of requiring users to install and maintain software on local devices, SaaS applications run on the provider's servers, accessible through a web browser. This model allows users to benefit from automatic updates, scalability, and reduced IT burden. With SaaS, organizations can easily manage licenses, collaborate in real-time, and access applications from anywhere, making it a popular choice in various industries.