The three main types of cloud computing are SaaS, PaaS, and IaaS.
Software as a Service, or cloud application services, uses the internet to deliver software applications to its users via a third-party vendor. Most SaaS applications run directly through your browser, which means you don’t need to download or install anything. You can purchase a basic, easy to set up solution right out of the box, or splurge for more complex solutions if needed. The vendor, rather than your own IT staff, manages all technical issues, including data, servers, and storage. SaaS include security and compliance as well as maintenance, and are scalable to the size of your business.
Platform as a Service, also known as cloud platform service, is mainly used for applications but also provides cloud components to certain software. PaaS is mainly used by developers as a framework so that they can create customized software and applications. PaaS platforms can be accessed by multiple users and run without extensive knowledge of system administration. All servers, storage, and networking can be managed by the enterprise or a third-party provider while the developers can maintain management of the applications.
Infrastructure as a Service, or cloud infrastructure services, offer self-service access and monitoring to computers, networking, and storage, among other services. With IaaS, clients can pay as they go for resources as needed, rather than buying hardware up front. IaaS uses virtualization technology to deliver infrastructure, which clients generally control through an API or a dashboard rather than through a physical data center.
To recap, IaaS provides a general data center as well as allowing you to host custom-built apps. PaaS is usually built on top of an IaaS platform to minimize the need for system administration. It allows the client to focus on the development of their applications rather than on management of infrastructure. And SaaS, which is generally built on an IaaS or PaaS platform, offers a ready-to-use solution (such as email or a website) to meet a particular business need.