In cloud computing, which component allows users to access applications and services over the internet?

The correct answer is Software as a Service (SaaS) because this model specifically provides users with access to software applications over the internet on a subscription basis. In the SaaS model, applications are hosted in the cloud and users can access them through a web browser, eliminating the need for local installation and maintenance. This accessibility is one of the defining features of SaaS, making it user-friendly and easily scalable, as it can reach a wide audience without the complexities associated with traditional software deployment.

In contrast, Infrastructure as a Service (IaaS) primarily provides virtualized computing resources over the internet, allowing users to manage hardware components, but it does not focus specifically on software applications. Platform as a Service (PaaS) offers a platform allowing developers to create, deploy, and manage applications without dealing with the underlying infrastructure, but it is not directly about providing end-user applications. Network as a Service (NaaS) facilitates the delivery of network services but does not pertain to direct access to applications. Thus, SaaS distinctly represents the component that allows users direct access to applications and services via the internet.