Public clouds are online services that provide computing resources, such as storage and processing power, over the internet. These resources are shared among multiple users and organizations, allowing them to access powerful technology without needing to invest in physical hardware. Major providers of public clouds include companies like Amazon Web Services, Microsoft Azure, and Google Cloud Platform. Users can easily scale their resources up or down based on their needs, making public clouds flexible and cost-effective. They are commonly used for various applications, including web hosting, data storage, and software development, enabling businesses to innovate and grow without heavy upfront costs.