Oracle ADF (Application Development Framework) is a comprehensive Java-based framework used for building enterprise applications. It simplifies application development by providing a set of pre-built components for building UI, data visualization, business logic, and integration with other systems. Oracle ADF is widely used for developing web-based applications, mobile applications, and desktop applications that are scalable, secure, and efficient. The framework is commonly used in the IT industry and requires specialized skillsets to operate and develop applications.